What should I replace my Sprint TP2 with?

[NYC Guy]

My Sprint contract is expiring the end of June and currently I am using the HTC Touch Pro 2 which is running on WM 6.5. Sprint is offering me $150 toward a new phone on 7/1, what models in their current lineup should I be considering? By the way, the reason why I selected the TP2 to begin with was because of the 5 row slider keyboard. I must have a 5 row keyboard similar to the TP2's highly rated keyboard in my replacement phone. The operating system doesn't have to be WM and I am open to the Android operating system but it must be a 4G phone!

Also if you know of something in the pipeline that is coming out in the next few months that is worth waiting for I can always wait and stay on a month to month deal with Sprint.