I own three pair of these pants! Very flexible and breathable. I'm 5'7 and about 165-170lbs and use the 32" waist in the short version.
Water repelling will repel dew or anything similar. If it's a heavy downpour you can expect your legs to get wet. However, it doesn't take to long for these pants to dry. I typically just hang them up at night and they are ready to go in the morning.
This little thing is flat out awesome. I was skeptical at first, but I won't leave home without it now. I don't use MSR canisters with mine. I use Jetboil (they are typically on sale when I go to the local store). I use a 1L cooking pot on mine and sometimes it can be kind of 'tippy'. Just ensure you have flat surface to boil your water or spend the $15 and purchase the stabilizers that can attach to the bottom of the canister.
I'm not entirely sure what made this bag not work for me. I took it out on a 25-30 degree night and slept awfully. I slept on top of a Big Agnes Insulated Air Core sleeping pad inside of a tent. I wore a basic base layer and wool socks.
I was slightly cold all night and never felt warm.
Fits inside my Field and Stream 'Eagle Talon' Kayaks from Dick's sporting goods. I ordered the medium size.
So far, I have no complaints