anyone? I'm currently doing some research of my own. I did pickup some nuggets of information.. Such as:

-polypro is a good option, and compares favorably to under armor. Duofold also is very good, but might be too warm. They have regular kind and the Varitherms (not sure which one is better). Some have a polyester layer inside and a wool one outside, others have cotton instead of polyester
-some people said underarmor is between a light base layer and wool since wool is a bit too warm. So maybe better off getting a wool shirt + any old base layer for the compression insulating effect.
-smartwool is a good choice..
-underarmor is a bit warmer than target's c9 champion shirts and walmart starter shirts, and the coldgear 3.0 is the warmest they have.
-theres also something from Walmart called Rocky which is good for below 30 degree weather. And something called a alertshirt.

anyways i'm still looking into it. I'm probably going to go to Marshalls and see if i can find a wool shirt or underarmor or duofold thing here. If not, than I'll get one of the options i listed. Maybe even the polartec tops idk. Theres just so many options and I need to rely on whichever one i get to keep me warm this winter.