you would first need to see what your needs are and what you plan on using on it. I worked with VZW and now At&t and alot of people ask which is best but its ont of those questions that depends on the user. I would use a Blackberry because of the push email which is very nice as well as that you can have up to 10 email accounts on the device. It does not have Windows apps on the phone out of the box but can be bought from 3rd party so it can then view, edit and create Word Docs and the such. Treo 650 is eally on good now for realtors due to the Supra key but now the newer versions of the key work with the newer PDAs. Not one for a PALM OS anymore since its pretty outdated. E62 is a solid PDA. Good features, works with Blackberry email and has the Symbian OS which does do word and execl stuff (just named differently). Who is your carrier? If its At&t, the BB and the E62 would be the better as the Palm 650 has pretty much fell out of favor and only those select few really use it. If you have questions about them feel free to PM me.