I kinda sorta agree with the above. I have a 100-wt fleece top from REI (not their brand though) that I love. It's like a second skin.

then there's the cheaper, Gander-mtn type. It's a knock-off, I think, of the USGI type. Relatively warm for its size, but it pilled real easily and got a bit loose at the cuffs and such. It was OK down to the 50s as sleeping wear, and great under a good jacket in 0 degree temps. But, I think a good heavy long john would have worked too. Personally, I enjoyed the top better as an indoor shirt, and the pants for actual outdoor use.

The nice thing was it had a front half-zip, and breathed better.