I have had two of these shirts for about a month now.  I live in AZ where the coldest it gets is about 39.  I work nights so i need to stay warm.  These seem to fare better than the Underarmour cold gear shirts that i have previously worn.  I don't know what the difference is, but it seemed that these just felt warmer.  No matter what i wear it seems to itch though.  I have to wear a under armour heat gear compression shirt underneath everything to stop the itching.  Probably just me, but whatever.