I'm 6'4 205lbs. I got a 33 waiste and the CR1s were my choice, and I have yet to complain about them. Great fit. I guess when it comes down to it it is more a cosmetic issue. the A4 seem overall a lil slimmer than the CR1 apearance wise.
matter of fact, I know a couple guys that went from the A4 to the CR1. They claimed the CR1 is actually a lil more comfortable and due to the higher bottom supports.
I personally like the look of the A4's and those are the ones i am getting. I am also tall and skinny, and when my buddy got them they fit like a glove to, he on the other hand being short and stout hatted to sit in them.