My wife currently has a BB and it is set up through her work on the BES. It is hands down the best work based phone one can own but what I don't like about it is the OS is plain and lacking. All her friends have BBs too so between them all most all models I've played with and the OS and UI layout is pretty much identical between them all. That makes it boaring that all BBs are the same... They do have a fierce following though and so apps are plenty, as well as tweaks but you have to re-learn the modding process.
Wife plans on getting a Palm Treo Pro to replace her BB soon as she doesn't need to be on the BES anymore (promotion). I can "do"
more to that one than her BB