I'll be finding out tomorrow night. I do not have an under quilt. As of today, I have no plans of getting one. I'm a 3-season camper, so it's typically warm enough at night. For my trip this weekend, the overnight temps will reach the low 50's. I have a HH Exped. zip hammock, stock tarp, sleeping bag, small air pad, and a large windshield sun reflector (I'll be using this for the first time). Theoretically, I should be okay. I'm bringing a space blanket just in case, figuring I could make an improvised UQ with it if I end up freezing my butt off.
I'm thinking I'll be alright.
Has anyone had a similar setup? Good? Bad?