Gear Review: All Hail The Therm-a-Rest MondoKing
Posted by Derek Newman on 2nd May 2023
We’ve slept on all sorts of sleeping pads ranging from ultralight inflatables to those odd foam camping mats that look like egg cartons sewn together, but we’ve spent the most time sleeping on the MondoKing 3D. With seasons upon seasons of sound-slept research, we only thought it fitting to explain why we’re crowning MondoKing as one of the comfiest, if not the comfiest, sleeping pads for camping. We’re also stacking it up against two other heavyweight camping mattresses, the Exped MegaMat and the HEST Foamy, so you can see exactly how it compares.
Let’s start by detailing the significant features that all sleeping pads have in common to see where the MondoKing succeeds and what it could do even better.
Quick Answer
The Therm-a-Rest MondoKing 3D is the most comfortable car camping sleeping pad in this comparison for side sleepers, thanks to its 4.25 inches of solid foam and vertical sidewalls. If you want a higher R-value for cold-weather base camping, the Exped MegaMat (R-8.1) or HEST Foamy (R-8.8) sleep warmer, though both weigh more and the HEST Foamy trades packability for true memory-foam comfort. All three excel at car camping and none are built for backpacking.
Comfort
We think the MondoKing is one of the comfiest pads out there. 4.25 inches of StrataCore foam combined with a plush sleeping surface makes for a full-on slumber fest. While most folks wake at the crack of dawn with hip pains from side sleeping, we can and will sleep in like we’re taking an actual vacation.
Some companies opt for air-filled foam in their high-end pads, but Therm-A-Rest uses a solid layer of foam for cushioning that lasts. It also makes a huge difference for side sleepers. The top has the same silky soft feel you’d expect from a fancy hotel bed, too.
Most pads taper at the edges, but the MondoKing’s vertical sidewalls keep a nice, flat surface to sleep on. That might not sound like a big deal, but when you’re struggling to sleep on your current pad and notice your elbow sliding down the tapered sides over and over, you’ll understand what we mean.
Therm-a-Rest MondoKing 3D Sleeping Pad
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Versatility
Between its weight and comparatively limited packability, the MondoKing isn’t a great choice for backpacking or trekking, but it goes above and beyond for every car camping trip and more. Winter trips to yurts and cabins are all the merrier, especially when the yurt’s mattresses look slightly questionable.
We even take the MondoKing when we rent hotels and houses with friends. If there aren’t enough beds for everyone, we gladly bring this pad along because it’s most likely the comfier option anyway.
And the MondoKing is a master in its own class for outdoor festivals. Dancing all night requires a good day’s sleep, which is next to impossible with standard sleeping pads. With the MondoKing, you’re in for a solid slumber for the next night’s dance.
Inflation
Therm-A-Rest didn’t skimp on features for the MondoKing, and the TwinLock valves offer best-in-class inflation. With separate valves for inflation and deflation, the MondoKing is quick to inflate or deflate.
The twist inflation valve helps you inflate this pad three times faster than with Therm-A-Rest’s classic valve design, and this sleeping pad self-inflates quickly and efficiently. Simply open the inflation valve and let the pad do the rest of the work. Of course, you can also inflate the MondoKing more quickly by using the included pump sack, which is helpful to ensure that your own breath’s moisture won’t collect inside the pad and ruin the insulation. The deflation valve is also designed a bit bigger and can open completely, helping deflate the pad five times faster than previous designs.
Both valves sit on the sides of the sleeping pad instead of the top. Again, it’s a small change that makes a real difference, keeping you from waking up with a face full of TwinLock valves.
R-Value
The MondoKing holds a solid 7.0 R-value, which provides year-round warmth worthy of summer camping trips and most winter excursions.
In the past, R-values were somewhat unreliable, but sleeping pad R-values were standardized in 2020, making it easy to understand the thermal resistance or warmth of a pad on a sliding scale. If you want to know more about sleeping pad R-values, check out our post on the subject, Understanding Sleeping Pad R-Values.
With a rating of 7.0, the MondoKing is plenty comfortable for 4-season use. Even in summertime, we like pairing a pad this warm with nothing more than a couple of blankets. Comfortably sleeping outside on a warm summer night with this pad and a blanket truly redefined camping comfort for us. If you need extra warmth margin for shoulder-season base camping, the Exped MegaMat (R-8.1) and HEST Foamy (R-8.8) both sleep warmer, which we cover in the comparison below.
Weight
With all that cushion, it’s safe to assume the MondoKing is one of the heaviest sleeping pads out there, and it is. Weighing in at 4 pounds 6 ounces for the Large and 5 pounds 8 ounces for the XX-Large, the MondoKing is actually heavier than some dual sleeping mats. And while it might be too heavy for your backpack, your car should have no problems carrying the load from point A to point B.
Packed Size
With a pad as big on comfort as the MondoKing, it comes with a larger-than-normal packed size. Packing down to 10.3” x 26” for the Large and 10.3” x 31” for the XX-Large, this pad could be called bulky and certainly takes up more space in our car than any other camping supplies. But, for what you get from this sleeping pad, the bulky packed size is a small price to pay.
How It Compares: MondoKing 3D vs. Exped MegaMat vs. HEST Foamy
The MondoKing isn’t the only luxury sleeping pad built for car camping. Here’s how it stacks up against two other favorites in our lineup, the Exped MegaMat and the HEST Foamy.
| Sleeping Pad | Best Use | R-Value | Thickness | Weight | Packed Size |
|---|---|---|---|---|---|
| Therm-a-Rest MondoKing 3D | Car camping | 7.0 | 4.25in | 4lb 6oz (Large) / 5lb 8oz (XX-Large) | 10.3 x 26in (Large) / 10.3 x 31in (XX-Large) |
| Exped MegaMat | Camping | 8.1 | 4in | 4lb 9oz (Medium Wide) / 5lb 11oz (Long Extra Wide) | 26.4 x 8in (Medium Wide) / 39.1 x 9.8in (Long Extra Wide) |
| HEST Foamy | Camping | 8.8 | 3.9in | 9.5lb (Short) / 11lb (Regular) / 13lb (Wide) | 25 x 10in (Short) / 25 x 12in (Regular) / 30 x 12in (Wide) |
The Exped MegaMat splits the difference between comfort and warmth, with a higher R-value than the MondoKing and a similarly plush recycled fabric top. The HEST Foamy runs the warmest of the three and uses genuine memory foam for a mattress-like feel, but its roll-up design makes it considerably heavier, especially in the Regular and Wide sizes.
Exped MegaMat Sleeping Pad
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HEST Foamy Sleeping Pad
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FAQ
What is the R-value of the Therm-a-Rest MondoKing 3D?
The MondoKing 3D has an R-value of 7.0, which covers three-season camping comfortably and holds up well in most winter conditions when paired with a warm sleeping bag.
Is the MondoKing 3D good for backpacking?
No, the MondoKing 3D is built for car camping, not backpacking. Between its weight of 4 pounds 6 ounces to 5 pounds 8 ounces and its bulky packed size, it’s best suited for trips where you don’t have to carry it far.
How does the MondoKing 3D compare to the Exped MegaMat?
The Exped MegaMat has a higher R-value (8.1 vs. 7.0) and a smaller packed size, while the MondoKing has vertical sidewalls and a solid foam core that some side sleepers find more supportive. Both are similar in weight and built for car camping.
How does the MondoKing 3D compare to the HEST Foamy?
The HEST Foamy uses genuine memory foam and has the highest R-value of the three (8.8), but it’s significantly heavier, ranging from 9.5 to 13 pounds depending on size. The MondoKing is the lighter, more packable option of the two.
What size should I choose, Large or XX-Large?
Choose the size that matches your height and how many people will use the pad. The Large measures 77” x 25” and the XX-Large measures 80” x 30”, giving noticeably more room for taller campers or couples.
How long does the MondoKing 3D take to inflate?
The MondoKing 3D self-inflates in just a few minutes and can be topped off even faster using the included pump sack, which also keeps moisture from your breath out of the foam.
Can the MondoKing 3D handle winter camping?
Yes, its 7.0 R-value makes it suitable for most winter car camping and yurt trips. For extra-cold conditions, the higher R-values of the Exped MegaMat or HEST Foamy offer additional warmth margin.
Conclusion
We think the MondoKing is worth its weight (and large packed size) in gold, and although it’s one of the most expensive sleeping pads on the market, a single night’s sleep on the MondoKing will cure you of any buyer’s remorse. And though it has a price tag that is more expensive than a single night’s stay in most hotels, once you have the MondoKing, you’ll be looking for reasons to skip the hotel and go camping instead. If ultimate warmth or true memory foam is more your priority, the Exped MegaMat and HEST Foamy are both worth a look too.
About the Author
Derek Newman
Born in the Wasatch, Derek has had an affinity for mountain life since day one. He was on skis the year he learned to walk, and as a high school graduation present he gifted himself rock climbing lessons. Nearly two decades later, Derek spends most of his time climbing up and/or skiing down most of the mountains around Salt Lake City, and he's traveled around the world multiple times for the sole purpose of peak exploration. When he isn't a man about camp, he's working in Campman's content marketing crew writing up blogs about backcountry skiing or rock climbing as well as describing products that he's used personally. He's climbed in most climbing shoes, toured on most backcountry skis, and ridden the resort on skis, snowboards, and even some evac sleds.
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