Hey Steve,
I've been using one since spring 2014 and I'm happy with it.  BUT, I've noticed recently that it's starting to lose air overnight, not quite to the point of laying on the ground by morning, but I'm not sure how long that's going to reman true.  I can't find anything causing it so I assume its the valve.

http://myselfreliance.com/wp-content/uploads/2015/08/sleep-system.jpg

Actually, I haven't looked into it yet, but the service centre is in Washington and takes 4-6 weeks for repair, so I'm not sure I'll bother going that route.  I bought it at MEC and they are very good about returns, for any reason, so I'll probably try them first.

"Your mattress is guaranteed without time limit against defects in materials and workmanship. Return shipping charges for the repaired mattress are covered. • Should the mattress be found defective under this warranty, Cascade Designs, at its option, will repair or replace the mattress. Mattresses older than two years from the date of manufacture may be replaced with a cosmetically irregular mattress. • "

I've heard of others buying a repair kit for the valve so maybe Thermarest will send me one if I ask.  I'll let you know how it turns out.

Other than that, the pad is as comfortable as any and if you can stay on the thing all night without sliding off, it provides good insulation from the cold ground, especially if you add a ground sheet under it to control moisture.  My bivy mostly controls the sliding issue.

I have the neoair all season.  I opted for the large version because I roll a lot at night. The mini pump is not the fastest thing in the world. The large is quite big in size.  The neoair pads do make some noise when you move around. You need to play around with the amount of air you prefer in the pad.  I've slept out in the snow with mine and it works good.  I use a down quilt and a liner with mine.  The warranty is supposed to be a limited lifetime. Thermarest is a cascade design company and which also makes MSR products

I just bought one and slept on it for the first time last week at Pukaskwa Natl. Park. Like Russ, I bought the largest one available, and am quite happy with it so far. Looking forward to putting it through its paces when the nights get colder. I'll update in this thread at the end of October.