I have a motorola v3 phone at the moment, I found that it looks great, but there are a few annoyances. The texting is a little sluggish, particularly on predictive text. You'd probably only notice this if you text quite fast, but it can get a good sentance behind me. This was improved somewhat by replacing the software on it with a new version, not completely though. Also, if you have a nokia currently, you may find yourself annoyed that it's much harder to resume a message you were working on earlier. With nokias you can just quit the message editor and when you return your message will still be there, not the case with the v3. Oh, and the inbox is way too small. Apart from that its a nice phone! Being thin is very nice in my pocket.
I'm not sure about current phones so i'll leave that to someone else.