stryder's idea to use the 2go trifecta as an improvised underquilt works well. Properly rigged, the trifecta provides deeps walls. In the summer, I'm find I'm fine with no topquilt, just a jacked. It is excellent for windy conditions, especially in the winter. For another application, see the revhiker chanel on youtube for a guy that uses a pair of trifectas + a pad instead of UQ/TQ. I think he's getting close to vapor barrier type effects, this is still on my to do list to try.