I have been on the hunt for a quality sleeping pad for some time, it is just really hard to find the nice stuff in the stores to try in my neck of the woods. My REI 3.5" pad leaks down at night, my Thermarest Basecamp leaks down at night, and all I am left with is a Big Agnes Air Core that is going strong, but not very comfortable. I did manage to find a Sea to Summit Comfort Plus pad to try out in store and it was comfy, but not thick enough for my side sleeping habits. I wish I could find a Megamat to try as I feel that gets the absolute most votes for comfort. This thread has been very helpful with suggestions, keep them coming!
You can do much better than the Big Agnes Air Core. That mattress was top of the line when it first came out, but it has been eclipsed by better mattresses since then. The Comfort Plus I think of as strictly for backpacking.
I slept on an Exped Synmat 7 (2.8" thick) on a Helinox cot last night as a test and today I spent some time on the REI Campbed 3.5, also on the cot. One fact was clear: A self-inflating mattress with a foam top surface is more comfortable than a non self-inflating mattress without foam. Air can support you and provide some softness, but air plus foam has a softer, more luxurious feel.
BUT: In any case where weight and packed size are important, a self-inflating mattress is at a big disadvantage. They're heavy and bulky by definition. So what's the most comfortable non self-inflating, insulated mattress you can buy, and how do you get around the inconvenience of having to blow it up?
After reading lots of specs I've decided to order an Exped Synmat Mega 12 MW. Specs:
4.7" thick
25.6" wide
73.6" long
2 lbs 8 oz
Packed size 6 x 11
R-value 5.3 (-4 degrees F)
This looks like a do-everything mattress. If you only want one mattress this could be it. It's slightly heavy for backpacking, but not intolerably so compared to the comfort of the width and thickness. It would be perfect for kayak and canoe camping, where weight isn't a factor (unless you portage long distances, but even there 2 lbs 8 oz isn't excessive). The width may fit on a Helinox cot and will fit on a Camptime Roll-a-Cot. Unlike the Megamat, it deflates and rolls up very quickly with minimal effort.
What about inflation? This year the new Synmat Mega 12s come with the yellow pump sack. It takes about 4 sackfuls of air to inflate a mattress in about one minute. Short of a battery-operated pump, I don't think there is a faster or easier way to inflate a mattress.
I don't know of another mattress that I could say with confidence that it works well for everything from backpacking to car camping. I'm pretty sure there is no other 4.7" mattress on the market that's light enough for backpacking.
The one drawback, then, is the lack of foam on the top surface of the Synmat Mega 12. But it's ***less than half the weight and just one-third the packed size of the Megamat!*** With the arrival of the Mega 12s, I no longer consider the Megamat a camping item. I use it strictly at home.
Kbahus, if you can't find a Synmat Mega 12 to try out in person, I honestly think you can order one sight unseen and have confidence in the quality and the comfort. The Mega 12 has easily 4 times the comfort of your Big Agnes (yup, I used to own a BAIAC too). I had to sleep on the Synmat 12 (now called the Mega 12 LXW) for months on a cot and slept very well even with hip and shoulder arthritis. I alternated with the Megamat and found it slightly more comfortable, but not enough to justify the greater weight, bulk, and inconvenience of rolling it up (not an easy job). Several camping retailers have excellent return policies if you don't like the Mega 12. Or order a Mega 12 and a Megamat and return the one you like less.
(Sorry all, I know I get carried away about the topic of mattresses.)