How low a temp can this bag be used for? I'm looking for a summer bag and could combine it with my micro puff jacket if I had to. Generally, temps no lower than the 40's, but mostly 50-60.

I have not used the cocoon 60, but I have used a very thin synthetic bag, iwth about the same loft.

I would rate it as a 50 degree bag with light shortsleeve hiking clothes. with an insulating jacket and windpants, it could be pushed to 40 depending on your comfort, especially if used in conjunction with a bivy sack (recomended with a quilt anyway because of wind and chances of convective heat loss)

I used my 50 degree synthetic bag at 10degrees once... but that is a different story.

Thanks, Ryan. It gives me something to work with in comparison shopping.