Agree with the others here, it comes down to what best suits your individual needs. Not just by way of phone features, but carrier coverage, pricing, etc.
When ever I am asked the "which is best question", I encourage researching a carrier's coverage maps and calling plan options, talking to people who have real customer experience with each carrier, and going to retail stores to get some "hands on" experience with the store display devices.
1st Step in Troubleshooting: Do you have a BlackBerry Data Plan?
2nd Step in Troubleshooting: Pull the Battery.