I just found this thread from some time ago. About three years ago I bought my set of Wiggy's sleeping bags. Now I know that the serious campers go with down but I'm such a fumble butt that I don't want to take a chance of looking at my sodden down sleeping bag and wondering how many days it will take to get it dry. I bought the two bag system called "Fortress" (ok, that's a little silly) the idea is you have two bags, one light and one heavier and when it gets really cold you zip the two into one really warm one. Now that I'm high mileage and a little brittle it takes quite a bit to keep me warm all night. No matter what, I sleep warm at night with the Wiggy's system. You knew that there is no free lunch right? Compared with down, the bags are bulky and heavy. There it is; no way to dress it up or to minimise the fact.
If your in the market for a bag I'd read the web site from one end to the other, lot of info there. I couldn't be happier with my bags and if the limitations of bulk and weight are something you can live with I honestly don't think you can do better. One last point: Wiggy makes the claim that you can leave the bags packed up in a compressed state without damage to the bag's loft. I pack and store my bags in a small blue barrel, every time I stuff them in it's a real wrestling match with the outcome by no means certain. The only way I can get the lid on is to hold the bags down in the barrel with two plywood pieces that form a "X" over the top of the bags. This isn't very scientific but over the time I've had the bags it hasn't gotten one bit easier, so I'm guessing the loft remains in fine shape.
Best Wishes, Rob