I utilized the Blackberry for 13 months before moving to the Treo 650. My complaints were voice level, color, and the control wheel. On the 650 I enjoy the touch screen with setting sections quick to access. In my opinion I feel the PDA function of the Palm is superior. The Treo, also has a handy download, Volume Care, that increases the voice and ring levels greatly which has been a benefit. I have read of phone shut-offs yet this has not been a problem for me.
Good luck on your choice.
Michael