Whats the best touchscreen with keyboard phone out there?

I have had my sidekick for little less than a year and I realized the mistake of getting it. Now I want a Windows Mobile phone. Any suggestions? I particularly want it to have a touchscreen and slide out QWERTY keyboard. Also, whats the difference between a smartphonen and a PDA? Also, how much does 100MHZ make on a phone? I have been looking at the T-Mobile Wing, but at overclocked best, is about 312(partially unstable) and 299(stable) while other factory tuned smart phones with touchscreen and keyboard are tuned at 400MHZ+ for factory settings. Does that make such a big difference? What phone should I get? Please include phones that can be unlocked for T-Mobile!