Haven't you grown out of that bag yet? I've worked at several outfitters over the last decade and everything I've come across has said not to store your bags compressed, it breaks down the fibers, down or synthetic. You're supposed to store the bag fully opened under a bed, or hung in a closet. Synthetic bags are usually cheaper and the only difference is the fill.
I've always tried to force synthetic bags on people, they're cheaper, they hold their loft better, and they don't develop hot and cold spots. The only people I haven't been able to talk into synthetic are Appalichain Trail Thru-hiker weight weenies. These guys cut all the tags off their gear, remove the embroidered stitching and leave the toothbrush, soap, and deoderant at home to save a few ounces of weight. The only advantages to down is that it is extremely compressable and lighter weight, only an issue if you're carrying a heavy pack and are tight on space.
I'm using Mountain Hardwear's base model sleeping bag I believe it called the 2nd Dimension. It's served me well over the last 4 years. I'm probably getting close to 200 nights in it. I mostly do weekend camps in the Smokies. The first year I had it I spent over 100 nights in it, I was a hippie.
www.rei.com is a good place to find anything, but I like
www.sierratradingpost.com better. It's prices are better than employee cost. Here's a great bag for anybody:
http://www.sierratradingpost.com/xq/asp ... roduct.htm $40 bucks, if you're tallker than 6'4" get the long for $10 more.