I have been using the EE Revo 10deg for the last couple years and really like it. I use an Exped Downmat 7 under it and have been toasty into the teens. The straps really work to tuck the quilt in around you, and the foot box can be zipped up and drawn closed for a pretty draft free system.
The biggest advantage IMO is in warmer weather when it is nice to have blanket instead of a bag. For cold weather camping you need to have your head/face covering system dialed.
I am a warm sleeper and do not expect to go back to a mummy anytime soon.
