I am about 6' tall with a 43" chest and 38" waist. I ordered an XL. The jacket fits exactly as I want and the sleeves will be long enough while riding. I haven't used it for bike riding yet, still too cold in the northern great lakes area. I have, however, taken a long walk with it. Temp was near 50 F with a little wind. It worked very well. I had a long sleeve T-shirt under and it was just about right. I started to sweat a little but not bad. Windproofing worked well. I believe I could still put a compression shirt on for a little more warmth if needed. 50* is about the limit I would go with this jacket, but that will allow the extra days of riding time I wanted. It looks good enough to just wear for any casual time.

Overall, I would recommend and am happy with the purchase.