Fits perfectly and breathes well
I've used this a few times, but I haven't had a really hot day (used 60-70). For all-day rides it's great to have extra coverage, and mixing various base layers and/or a vest makes this super versatile. While not really meant for cold, the long sleeves are just enough to take the edge off of a cool morning ride. I just wish there were more bright colors for visibility on the road. I'm 6', 160lbs with a 38" chest and 30" waist. I bought a small (The small feels more like a race-fit, and when I'm riding I don't notice the jersey at all... which is exactly what I like).
Love these jerseys. Nice on the bike fit. Sleeves are a little tight but I like that for a compressive fit. Light enough to wear in the summer to provide sun protection without overheating.
Big fan of this summer-weight long sleeve jersey. Great for protecting your arms from sunburn on days that are not ridiculously hot, but with a warmer base layer (merino!) or a wind vest, I've been comfortable down to 55*F. Coastal Fog color is a really pleasant light pastel blue that helps you stand out on the road without violating everyone's eyes with day-glo yellow. Keep in mind that this is a pretty slim-cut garment, meant to be worn in tandem with bib shorts. Taller folks who don't wear bibs will be at risk of having their navel poking out, the jersey is not cut that long in the front (but consequently doesn't bunch up in the stomach region).