What made me switch back after several months of Evo use was missing the email handling of the BlackBerry. Nothing does messaging like a RIM device.
This is the whole reason why I have been hanging onto my Blackberry. Really, nothing does e-mail like BB. You would know better because you actually used the device. I am planning to take a look at my co-worker's iPhone 4 to see how it does exchange to get an idea, but I am thinking that I can never do without a physical keyboard.
The e-mail is so fast and with full of keyboard shortcuts, it is a no-brainer.
Did you check if they have keyboard shortcuts? Like I for filing, F for forward, U for next unread or P for previous, etc.. Some people may take these for granted but it is just excellent. Space or Alt+Space.. Or selecting text, I would never try to select data using a touch screen, it is just like a joke. Was there a cursor on screen that you could use with keyboard or something else? I think there is another Android device with an additional Touchpad, right?
Which Android phone users choose really comes down to the manufacturer selection and hardware features nowadays. After all they all run the same OS (or same one you can probably root to get)
I would really like to hear more about your Android experience.