Well, it seems that I always keep coming back to the Treo 650 no matter what other device, or devices, I try.
I recently tried a Cingular 8125 for about three months. While I liked the keyboard, WiFi, and web browsing experience on the 8125, I really missed the one-handed operation of the Treo 650. In addition, I missed the keyboard always being available. It is just quicker getting things done with the Treo.
Anyway, I am back with another Treo 650, and I am glad!