I usually skip a generation or two when upgrading.
With all the crap I hear about how slow EDGE is, it really isn't that slow to annoy me. Yes, it does take a while to load up web pages and to download/send mail, but I don't use it that often to complain about it. I primarily like my iPhone because of its ability to store all my contacts very easily and allows me to listen to music. The ability to send/receive email, surf the web, etc. are all nice features, but not a necessity for me.