If I'm correct, SureType is available on the Pearl since it doesnt have a FULL qwerty keyboard. You wouldn't need SureType on the Tour, since theres a full qwerty.
I like it a lot. For me (not being a good speller or typer) it is faster.. Also found out that if you mispell a word you can move the curser back to the word and hit the trackball and it gives you the correct spelling
I upgrade to the Tour from a pearl. 50v 7.8 makes the Tour a very stable and fast phone. Untill official 5.0 comes out it is the only way to go. Just my opinion
You don't need suretype as you have a full qwerty. The predictive text input is available on the 5.0 OS, but if you're good with the keyboard, the predictive text will just slow you down, it doesn't make much sense to use it. If you have a touch screen, or non-qwerty i would understand.