The Kelty keeps me warm down to 32º. I've used it in the mid-20ºs, and while I wasn't toasty warm, I wasn't really cold either. At those temps I laid my down coat over top of it, mostly because I had it with me, and then I was toasty warm.

The comfort rating for that bag is either 30º or 32º. I'd say that's pretty accurate for me, and I'd say I sleep a bit cold compared to some people.

I used it two nights ago when the lows were in the mid-50's and with it zipped only about half way up I was very comfortable.

Personally, I am very happy with the Kelty Light Year Down bag so far. Unless it starts coming unraveled at the seams I expect be happy with it for many years to come.