From personal experience, I wouldn't get the Sidekick. I've had the Sidekick '08, and T-mobile has had quite a few problems with sidekicks. Data has been erased, contacts removed, and the time & date have been reset multiple times. The service is lacking - there's a T-mobile right by my school and I don't even get service! I barely get service anywhere. Also, the battery dies out quickly. All I know is that when my contract is up, I'm switching from T-mobile.
-Delta