I've had the same body for probably about the last 20 years - tall, lanky but not really what you'd call "skinny".  In fact, I'm kind of pear-shaped around the middle.  I never considered skinny jeans before because of that.  I've been wearing 505's for years, but have tried various other brands before that - nothing fit right.  Pants sit naturally below the waist on me, and at my 36"-38" waist, the legs were always really baggy.  I always looked like a wannabe gang member or something wearing jeans - even jeans that were very tight around the waist.

But I tried a pair of these at a store and they fit perfectly!  They sit naturally where pants want to sit on me, and there's no extra bagginess either in the legs or the butt.  (I have no butt, so this is important.)  With a 36" waist, they're cut so they do not look "skinny" with my legs, but they actually make me look thinner.  And they look really good with boots.  ("Boot cut" jeans look ridiculous with boots in my opinion; boots need a tapered leg, not a flared leg.)  In other words, they just fit right!

I bought a pair of the black stretch, which actually get somewhat loose after repeated wearings.  I tried a pair of the rigid 511's in a store, and I'll buy them next to compare.

In short, I'd recommend these not just for really skinny guys, but also for guys who have that middle-aged pear shape.  At the larger waist sizes, the legs are roomy enough that they just look like regular jeans, and they don't look like you're wearing "dad jeans" like the regular fit stuff can.