a) what's your usage allowance - how many MB's are you allowed to download each month of your payplan. You'll need approx 5MB / day if you're going to use a lot of BA. (that's with your view settings set to text and only ever fighting - no reading the boards).
b) does the phone support web browsing, not just the WAP content you get from most providers, but actually web browsing.
c) to avoid the hassle I had, (see this thread) can you actually play CB? - I'd advise you get the shop to show you it in action.