K2 Base Camp are selling Exped sleeping mats at really good discounted much cheaper than other retailers at the moment. Note that their 10% code (joining mail list) don't work on these sale items.
Exped mats are top quality and come with a 5 year warranty. Though some people do report of blown baffels.
My personal recommendations would be the ones that come with the yellow pump bag (schnozzel bags) as they are $50 purchased seperately and inflate much faster than the integrated pump mats:
Camping mostly in areas above 10 degrees at night - Exped SynMat XP 7 Long Wide
Camping mostly in areas below 10 degrees at night - Exped Downmat XP 7 Long Wide