Well I can't speak to the Pearl's keyboard from daily use, but I can talk in general about going from the 8700 to a SureType phone. I had an 8700 die on me, too, last fall due to water damage. Oops.
I got a 7130c and I really like it. SureType took a few days of adjustment but once you get the hang of it, it's not bad. It's still head and shoulders smarter and faster than T9, which I loathe.
I am looking to get a Pearl, too, because the 8800 is too wide for my hand and I'm not sure the 8300 does it for me, though the keyboard on that looks great. Sigh.
I find that SureType is a matter of personal preference, so try it for a week and see what you think. If you hate it, return it.