I ordered the "past season color" asphalt gray (another of the same color replaced it, go figure) in a Medium. I'm 6ft tall, but fairly thin at about 155lbs. Comparing my measurements to the size chart I seemed to be about a 1/2" under the listed size for the Mediums and since there were no Larges available at the discounted price, I decided to give it a go. Honestly, I was a little worried it wouldn't fit ... especially after trying on a coworker's NF jacket (different jacket though) which was an XL and while it was big in the chest, the sleeve length was just right. Well, I was very pleased to find that the Medium Apex Bionic was a perfect fit for me! The sleeves are the perfect length so they don't ride up when I extend my arms or anything and the size through the chest and shoulders was just right for my narrow frame. I haven't really worn it in colder weather yet (only in temps in the 40's and not for extended periods) but I think it will be just what I'd wanted ... a nice, light-weight jacket to break the wind and provide some additional warmth on chilly days. I'm not expecting it to be a super-warm, go-live-with-the-eskimos type jacket so the reviews that knocked it for not being really warm didn't deter me ... and I'm glad! As another reviewer here or elsewhere pointed out, the zipper pulls on this particular jacket are orange. I like 'em. And one of the reasons I wanted this type shell over a fleece was that it isn't a pet-hair-magnet. I love my dogs, but if i wanted a fur coat, I'd buy one. Unfortunately, that's what all my fleeces have turned into, so this one has been much loved already for it's ability to stay fur free. My only complaint, and it's a minor one, is that the color doesn't stay down as nicely as I'd like. Not a fan of the popped-collar look unless I need it up to block wind so I'd rather it lay flat when I want it to. Still doesn't change the fact that I recommend this jacket!