Here's another reccommendation for Wiggys. I've done a lot of backpacking, camping, and have even spent nights hanging from the face of climbs such as El Capitan, and my wiggys bags have been there with me.
The best reccomendation I can give is to determine what your uses will be and what temperature ranges you will be in. If you're like me, and are in an area where winter and summer are very far apart, you may want to either buy two separate bags(one for summer, one for winter) or a convertible system. A convertible system is either one where it has an insulation layer that can zip off, resulting in a lighter bag when the extra insulation is not needed, the main bags that come to mind is the Sierra Designs Metamorph and Spectrum. There are also multibag convertible systems, the best example that comes to mind for this is the one made by Wiggys upon request by the Navy Seals. Known as the FTRSS(Flexible Temperature Range Sleep System), this consists of an overbag and a regular Wiggys sleeping bag, like the Ultra Lite -20F or Super Lite -40F. Using this system, you can use the overbag by itself as a bag rated to +35F, the regular bag(rated to whatever it is rated for, be it 0, -20, etc), or mate the two bags together and have a very good system that is very warm.
Looking back at the first post, and for air mattress camping where weight won't be much of an issue, you can't go wrong with the Wiggys Hunter Model, it's large, comfy, and you'll never have problems being cold. If your area gets warm in the summer and stays warm at night, the wiggys Desert or Nautilus would be a good choice.
Also, there is nothing wrong with REI brand sleeping bags, and the nice thing about REI is that in their stores(a good place to visit) they'll let you crawl into the bag you're looking at, to make sure it fits, as well as being able to give you reccommendations based on your area(remember, lots of REI employees work there primarily for the discount).
Well, there's my 2 cents.
TC