BzBrianwrote a review of Patagonia M10 Jacket - Men's on March 22, 2016
Familiarity: I've used it several times
I was super stoked to get the M10. I've always heard super rad things about it, boasting its place as among the lightest 3-layer hardshells on the market. However, the fit really bothers me. Torso is too short, and hood is too small.
I'm 6'2, 180 lbs. I've always been a medium in Patagonia. The chest and arms fit great, it allows me to layer a R1 hoody underneath and if necessary an UL down jacket. However, the torso is too short. I don't have an especially long torso or anything, but my other Patagonia pieces in size medium are longer than this M10. Seriously. When I layer the Patagonia UL down jacket underneath it sticks out on the bottom, or worse, the M10 rides up. It's weird. When I have a harness on, it rides up and out of the harness and has a hard time staying tucked in.
Next, the hood is too small. The description says the M10 has a helmet compatible hood but there's no way I can layer a helmet underneath. Granted, I have a bigger than average head but previous helmet-compatible hoods worked for me (Super Alpine works). I have to layer it awkwardly underneath my helmet but it's in a weird zone between too big to go under a helmet and too small to go over.
Otherwise, the feel of the jacket is really cool. It's really interesting that a 3-layer jacket can be this thin. The lack of pockets doesn't bother me, if it does than you're probably looking at the wrong category of jackets. The single chest pocket is really all you need. How often do you really stick things in your pockets when you're climbing? If you want a place for your gel or phone, just put it in the chest pocket. If you want somewhere to put your hands, then the new M10 (2016) has that.
Overall, if you're able to get a great deal on this (I was) then take it if you can deal with its faults. If you want the best hardshell that is equally light, take a look at the Arcteryx Alpha FL if you can afford it. I'd still stick with this since it's way better value and Patagonia will help repair all the damage you inflict on this jacket (you will tear it up if you use it right).