Love these pants. I'm a bigger guy (Not fat, but not pencil thin like a lot of riders I see) I usually wear L or XL in most board pants that I buy, but after reading reviews and seeing the word "slim", I figured I'd go for the XXL. This is the first pair of slim snowboard pants that I own that don't death-grip my legs! The XXL is actually way big on me but I like the roominess without the extra material that most regular snowboard pants bring. I could defiantly fit into the XL's but want to layer up and sag a tiny bit. If you're a bigger dude (in comparison to most riders) I'm 6'1 and usually wear a 36-38 pants and the XXL of these are huge, so there is something for you to compare to.
Pants-wise: The material is thin but warm. Has a little bit of stretch and give; similar to what you would get from a softshell pant without being a softshell. It's summer, so I'll have to wait and see how they do in the snow!