Let me start by saying I've been looking for a shirt to match the quality and performance of the Columbia Titanium convertible pants I purchased while in Australia in 2008. I've had a few false starts due to sizing, but I think I've finally found what I've been looking for.  This shirt will keep the UVA/UVB rays off of me while in Arizona, which is my number one concern.  The roll up sleeves are a tiny bit bulky at the elbow (sure do love those zip off pant legs, kinda wish Columbia made shirts with zip off long sleeves), but that's pretty much of a nit-pick.  The shirt fabric seems to be a little bit warmer than the Titanium pants fabric, but not so much that it becomes a big issue -- just a little bit of one.  I usually wear XL Tall in most shirts, but this shirt is sized so that XL works best for me. Columbia's shirt sizing seems to be all over the place, depending on which style you choose.  The fit of the Tamiami II in XL, though, seems to be closest to what I've seen in shirts of other brands, with perhaps just a little more length in the sleeves than I need (maybe 1/4 to 1/2 inch) and just a touch less than I'd like in the body at the sides (but I like the sides to be pretty long, so maybe that's just me).  Not perfect sizing, but pretty close to perfect.  And this is a very, very comfortable shirt in terms of feel and temperature. All in all, a good shirt that seems like it will be durable, comfortable and offer good protection from the sun.