this guy kept me bone dry during the maroon bells' monsoon season while doing the 4 pass loop, and for that I am grateful. i use this jacket far more often than i expected to, and believe it a great jacket for the price. the only complaints (and why 4 not 5 stars) is that the hood is quite small, and and DWR seems to be wearing off quickly. 6'2" 175 and the large fits well, maybe a bit baggy, but nice for layering underneath...

Pros: keeps you dry, has pit vents, material is pretty solid, and has a slimmer fit.

Cons: material is a little sticky when putting your arms into the sleeves, sleeves are always tight at the cuff.

First off, this is not a "bombproof" rain jacket. It's not your end-all be-all of waterproofness.
That being said, for the price this is one of the best rain jackets you can buy. The features on this jacket are really dialed in: reinforced storm hood with plenty of room but not too big, longer backside to cover the butt, underarm zips to dump extra heat and humidity. It also packs small (smaller than a nalgene if you're good) and is lightweight, so there's no excuse to not bring it on your next trip. The fit is good too, I'm 5'10 145lbs and a medium fits well with room for layering.
If you're in the rain all day then keep looking and spend a little more money. But for a lightweight insurance policy against sporadic storms and mountain wind, there's no better (or cheaper) jacket.

not very breathable, but i got it on s&c for a good price. worked fine thus far in light rain, but i don't see a problem with it working in a downpour, everything is sealed. Jacket's look surprised me, it looked a lot better than I thought it would. SIZING: I'm usually sort of inbetween medium and large sizes for everything. I'm a guy, 6 feet tall(exactly, without shoes), wingspan about 6-2. 175 pounds, and I got a Large, it's a perfect fit for me. So it's on the smaller side, sizing wise.

I have used this in a few rainstorms, nothing too serious, but it held up great. The construction quality is good, and I didn't notice any leaking on or around seams. The hood is a little big, but is probably great for use with a helmet. I am 6 foot 165 pounds. I went with a Large because I have abnormally long arms. The overal fit is a little baggier than I was hoping for, but the sleeve length is good. Drawstring around waist is nice and hand pockets are a good feature as well, without adding too much weight.

I was curious about weight for this so I called Sierra designs about it. A medium weighs 15 oz. they told me. Just in case others were curious as well...