If you’ve ever camped when it’s cold out, whether that be in the winter or in the shoulder spring / fall seasons, you know how important a good sleeping pad is. While a sleeping bag’s temperature rating is important, I would argue that a sleeping pad’s R-value is even more important for camping in cold weather. Yes, sleeping pads help you stay comfortable on hard or bumpy ground. But even more importantly, sleeping pads insulate you from the cold ground. This insulating quality is measured with what’s called “R-value.” This article does a great job of summarizing what R-values are and why insulation through your sleeping pad is important in the cold. In a nutshell, much of your body heat is lost when sleeping on the cold ground. The more insulated your sleeping pad is and the higher the R-value, the less body heat is lost to the cold ground. This means a warmer night’s sleep.
The ideal R-value for cold weather camping is 4 and above. Sleeping pads with R-values suitable for cold weather camping often run well over $100. But there is one sleeping pad that stands above the rest in its affordability and insulating capability – the Kelty Mistral SI sleeping pad.
With the Kelty Mistral SI sleeping pad, you are getting a 4.7 R-value sleeping pad for under $50. The major drawbacks are weight and size. It comes in at 2 lbs, 12 oz. While not monstrously heavy, it is heavier and bulkier than more expensive competitors. For comparison, the Klymit Insulated Static V sleeping pad – one of the more popular cold weather sleeping pads on the market that packs up much smaller than the Kelty – boasts an R-value of 4.4 and weights a mere 1 pound, 8 ounces. But the Klymit costs twice as much as the Kelty!
While the Kelty Mistral SI is not an ultralight or minimalist sleeping pad, it can be used for backpacking. Whether you use a larger pack to accommodate it, or find a way to strap it to the outside of your pack, it can reasonably be brought backpacking. I’m speaking from experience because I brought the Kelty Mistral SI sleeping pad on our late October Appalachian Trail trip where nighttime temperatures dipped into the mid 30s. I was originally planning to bring an ultralight pad, but when I looked at the forecast I was worried my Snugpak Sleeper Lite sleeping bag – with a comfort rating of 32 degrees – wouldn’t cut it without a better insulated pad. So I changed gears last minute and brought the Kelty Mistral SI. I was toasty warm all night and slept like a baby. I attribute this more to the sleeping pad than the sleeping bag. I would not hesitate to bring the Kelty Mistral SI on any and all cold weather backpacking trips in the future. Would I like something lighter and smaller? Sure… Would I through-hike the Appalachian Trail with it? No way! But I don’t want to dish out the money to get something smaller and lighter, so I cope. If you’re car camping, this sleeping pad absolutely shines. The major drawbacks I noted – size and weight – are moot when car camping.
My only real complaints, since I’ve come to accept the size and weight challenges the Kelty Mistral SI sleeping pad poses, are related to the shape and straps it comes with. This bag could shave some serious weight if it were mummy shaped. Sure, the Kelty Cosmic SI sleeping pad is mummy shaped – but it only has a 3.9 R-value and costs $20 more. If the Kelty Mistral SI were mummy shaped, it might be damn near perfect for the price.
The other issue is the elastic strap it comes with. I would prefer a strap (or multiple straps) that have some compression / cinching capability. The elastic strap doesn’t help minimize the size of the sleeping pad when packed. You could absolutely buy your own improved straps to address this, and maybe I will one day, but Kelty could make a major improvement by including better stock straps.
One thing to be aware of – while this is a self-inflating sleeping pad, it will require a number of breaths to finish her off before closing the nozzle. This is common for pretty much all self-inflating sleeping pads, so it’s not a negative feature – just something to be aware of.
It is also pretty tricky to roll back up. I kept finding that as I rolled it up while folded in half, the fold would shift. You have to compensate for this by constantly pulling the fold back into place as you’re rolling, which can be tricky to do while also applying pressure to compress the rolled size. Just go slow and constantly make adjustments and it will roll back up just fine. But I find that it takes a bit more effort to roll up than some of my other sleeping pads.
- Warm and toasty
- Great for car camping
- Workable for backpacking
- Heavier than competitors
- Bulkier than competitors
- Rectangular shape
- Elastic straps aren’t great
- Can be hard to roll up
Rating: 4.5 / 5
While the Kelty Mistral SI sleeping pad has some drawbacks compared to the technical specs of its competitors, the price is unbeatable for a cold weather sleeping pad. Despite the drawbacks I noted in this review, I’m still giving it 4.5 stars for this reason. Yes, it’s heavier and bulkier than its competitors. But it’s at least half the cost of its competitors. There are also some improvements that could be made to the shape and straps it comes with. But these flaws can be forgiven at the price point this sleeping pad boasts If you’re camping or backpacking in cold weather on a budget, you won’t find a better sleeping pad for the price. I highly recommend this sleeping pad. I can personally attest it helped keep me toasty on a backpacking trip with nights into the mid 30s. If you’re looking for a budget cold weather sleeping pad, and you don’t mind the extra weight / size and some minor inconveniences along the way, you’ll be very pleased with the Kelty Mistral SI sleeping pad.
NOTE: At the time of writing this review, the Kelty Mistral SI sleeping pad is on sale at Ski Shack. You need to add some other gear to get free shipping and make the discount really worth it. But something to note if you’re trying to save yourself some money on this pad.
If you have experience with this sleeping pad, please share your thoughts in the comments below. If you have another budget sleeping pad recommendation, go ahead and share that with our readers in the comments. Happy adventures!