I'm pretty sold on this shirt, even though the zipper came to my door undone, alas I had the zipper functioning perfectly within a minute. I purchased this piece right before a 15 mile trail race up in the Jemez Mtns. above Los Alamos, NM. Temps at race start were in the low-mid 30's with a light breeze for the duration of the race. I found this piece to be the perfect semi-technical article of clothing for the cooler conditions and running at a race pace for 15 miles didn't pose a problem for moisture and heat management. The fabric breathes quite well and the zip on the neck and upper torso is perfect for self regulation of heat. The Impulse shirt feels excellent next to skin as I have worn it, no irritating seams. Thumbholes are the winner for me as is the napoleon chest pocket for a gel or two and your key. Throw it on, go run, hike, ride, whatever high output activity you can muster in conditions from low 60's to freezing. Note, I'm 6'0" and weigh 157lbs. with a slightly "trunky" torso and found the medium to fit quite well, hindsight I would have gone with the small as this shirt was purchased for trail running solely and the medium gave more loose fabric than I typically use for my running gear, I like a more athletic fit and snug is good in my opinion for that. However I can easily throw this over another layer and grab a cup of coffee in town and not feel like a superhero on parade. So I would consider the cut to be semi-fitted. Great article of clothing from TNF.

My favorite running/hiking/backpacking shirt ever. I have 3 of the 2008 version, and I grab them whenever the temp dips below 65. I'm 5'10" 160lbs, medium shoulders and lean torso, and the medium is spot-on in every dimension. The collar is high enough to keep out unwanted winds, but low enough that it doesn't rub on the neck when moving quickly. The 1/4 zip is more like a 2/5 zip, which is really handy when you need to cool down in a hurry. There isn't any pesky shoulder stitching, which makes it "pack friendly". And the thumb holes are key on those exceptionally brisk or wet days to keeping your hands from numbing up. Perfect shirt!