I've always been happy with all my Dakine clothing and this jacket doesn't disappoint. The fit and quality of the jacket it really good. It breathes really well, even with a pack on. The arms get sweaty, but I think most jacks of this type are like that. I just loosen the velcro at the wrists to let air in and that helps ventilate the arms. The vents on the side of the jacket do a good job at regulating temp too.
The length of the jacket and the cut are good. I am 5'11", 155lbs. I got a medium and the jacket fits perfect. It's not too baggy, but loose enough to stay dynamic and the length is good so you don't show crack. During high speed runs, the jacket doesn't flap in the wind. The tail of the jacket has a rubberish liner to help from riding up.
I used this in light rain the other day. It did an alright job at keeping me dry, but some moisture still got through. Mostly in the arms, but that could have been from sweat too. If you are looking for a jacket that is waterproof for riding in rain, then look elsewhere. But for a jacket to use on the those cold mornings, dewy/light rain, to cut the wind and packable...then this jacket is perfect.