I've only owned it a few weeks, but have worn it every day. It is sized as described (visit the Columbia site if needed). It fits snug, Currently I would recommend to anyone. I may someday even buy a second one.

Edit: I just spent two hours outside working on the lawn in 48 degree partly cloudy weather with this and a base shirt (<a data-hook="product-link-linked" class="a-link-normal" href="/Minus33-100-Merino-Wool-Base-Layer-705-MidWeight-Crew-Neck-Top/dp/B0006FK2QG/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">Minus33 100% Merino Wool Base Layer 705 MidWeight Crew Neck Top</a>). I would occasionally feel a slight chill; but overall it was sufficient.