I've got a GS. It gets amazing gas mileage, is really nimble, has great throttle response and is a lot of fun to ride on back roads, both sealed and unsealed. I haven't ridden a wee so I can't say much about it other than I sat on one and it seemed physically much bigger than the bmw. Try both of them and decide after that.
2014 350 EXC-F
2006 Djebel 250XC