Which way do you push the undercover when you get in? I ask this because I've tried both with varying degrees of success.
First, let me explain left/right. If I stand at the foot end, looking toward the head, the knee section is to my left and the head tie out (short bungee) is to my right.
If I push the undercover to my left, I find that the head section pulls a bit toward center so that when I get in, the short bungee is under a fair amount of tension. This pulls the head tie out down, collapsing the bug netting onto my face.
If I push the undercover to my right so that the long bungee is under tension, I manage to keep the bug netting off my face (I'm a left side sleeper) but my right shoulder is a bit exposed.
I've gone back to pushing the undercover to the left, rotating 180 degrees as I sit and then the foot section snaps back into place fairly easily. I wish I could figure out a better way to adjust the torso placement.
That said, the system appears to work reasonably well. On a recent trip to northern Minnesota in JULY, a nearby town reported a low of 40 F. I don't know if it got that cold where I was but it was definitely in the mid to high 40s. I slept in a thermal underwear (REI), socks, a 32 Western Mountaineering summerlight sleeping bag, and the undercover system. I was fairly comfortable but I did have to pull the hood up on my bag and cinch it down.