starkat wrote a review of Lafuma X 650 Pro Sleeping Bag: 40 Degree Synthetic on May 15, 2008
I chose this bag to include in my UL summer base pack. It's super light, packs really small (actually comes with a pretty useable compression sack), and while it's light, seems durable enough to stand up to some abuse and not complain too much. I paired mine with a silk mummy liner and tested it out in my backyard on a 33 degree night and was comfortable enough that I never woke up due to the cold, and there didn't seem any cold spots.
For summer/autumn camping, this bag can't be beat. Footbox is spacious. Zippers don't seem like they'll have snagging issues. The only problem I had with this bag is that there's a small pocket on the inside that uses a Velcro closure that might chafe your mummy liner the wrong way. I took that Velcro piece out with a stitch remover tool, problem solved.
Lafuma did really well designing this bag.