Actually, I went to see the Berghaus rep, and they're bringing out a new back system, which has a wicked drying thingy (but you'll all hear abuot it soon enough - well within the next year), and they also have an adjusable, and yet fixed back system. Bascially you put your kit in, try it on, and see if it fits. Then change it to be more comfortable, and when you have it perfectly comfortable, there will be no need to change the back at all! It's pretty good, but nowhere near as good as their new back cooling system. I can't tell much (as it's hard to explain it), but when it comes out, all the other companies will be stealing it, sorry, changing their cool back system, to something totally different (which will be exactly the same).