I wish I needed some of these...I'll add testimony on them to those considering it; I've used this sleeping system for most of the past 15yrs while in the USMC and it is a phenomenal setup, particularly at this price.
I don't need any b/c I long aqo acquired the components to have enough for me and the family. I do use a snugpak (with the goretex bivvy) when I'm going light, but that's just a personal preference as the green bag is pretty light.
Having used these all over the US, N. Africa, Europe, Iraq, Kuwait, and Afghanistan (in winter) I will def affirm that they are worth the $$$.
r-
Ray