I made a 5.0 quilt recently and just finished my first backyard test with it. Temps only got to mid 50's and I was very warm. Even had thoughts of venting. I have read that the 5.0 should get you well down into the 30's. We'll see. I am a cold sleeper, so hopefully it will at least get me down to upper 30's with warm clothing. I posted the quilt with pics on Hammock forums, below is specs and link to post. Hope this helps.
66 x 54 tapered to 42" at footbox
Weighs 22oz with stuff sack.
Digital Camo 1.6oz outer shell
Olive green 1.1oz for inner lining
5.0 oz Apex Climashield
Sewn in loops along long every 8"