My company is currently evaluating replacements for the blackberry. Well they where until the lawsuit get settled. But we looked at the treo and a number of other WinOS based PDA/Phones. I would take a look at the Motorola Q it should be coming out soon unless you use verizon since they have to screwed with it to get it locked down and working on their network. As for the difference between the 650 and the 700 well it really is a perference wether you like palm OS or WinOS.