I started off on the Brinkmann Gourmet Charcoal Smoker for a year. I then upgraded to the WSM 18" and never looked back. I'm a firm believer in smoke with what you got. If the Brinkmann is more in line with your budget, then go with it. You will put out some great Q. If you can swing it, I say go with the WSM. The extra size is very nice as well.
WSM, Mini WSM, Weber 22.5" OTG, Weber Jumbo Joe, Weber Smokey Joe, Brinkmann Gas Grill