Thought I'd share my short experience with Smartphone 2 (Before I sold it!). I found the MS Mobile 03 OS to be quite buggy, several apps would lock up on me and require a hard reboot (battery removal) to restart. (ie: phone wouldn't even power off via power button.) My Sandisk 512 meg SD card could be read from but not written to by the phone - so had to use external writer to dump mp3 etc. None of the apps have an 'exit' option in their menus and some Apps (media player) keep on playing/running when you think you've quit the app. It takes a lot of drilling down thru menus to get to what you want. Inbox and calendar are handy on first level menu but Tasks for some reason is on second or third level. My main gripe with phone is the keypad - even though it has blue backlighting, its almost impossible to see the letters on buttons for texting, in dark situations. T9 text option is hard to find too - it doesn't appear as an option - you have to press '*' then '4' to get it. Only find this out thru google research. The fact that it comes without any built-in doc reader/viewer software is pretty naff - it is supposed to be a pda/phone hybrid, so people would expect to view word docs etc on it. (The Symbian and Palmone smartphones come with doc viewers I'm pretty sure)
My likes? The instant outlook update when phone is in cradle is excellent - sure beats Palm hotsync. Screen quality is good and battery life was better than expected - the rom update must really fix the battery issue.