I have an E90 330xi as my "beater"/DD and I enjoy it very much. Handling and driving is very good and one can tell it's more refined than the E53

. I had to get the 330xi as 335xi had not been released back in April last year

, however I've driven the 335xi back in Germany and it's a great car (eventually might swap mine in a few months) and has lots of potential for interesting aftermarket upgrades ... (the engine has a very strong bottom end and will certainly be "responsive" to some remapping

) and well worth its money . Only "downside" for me is that I've (once again) made a few changes to the stock car/appearance and transferring them over to a 335xi would take some effort . I've started to post notes what I've done and if you need ideas you're welcome at
http://www.janixworld.com/330xi/
As you're mod mania as well you might be interested in some of the mods
- stealth K40 installation
http://www.janixworld.com/330xi/k40/
- Black Alcantara headliner/trunk and CF interior
http://www.janixworld.com/330xi/headliner/
- Hartger Classic 2 19" wheels
http://www.janixworld.com/330xi/wheels/
- Didn't yet have time for the Stereo section but you can at least find pictures at
http://www.janixworld.com/330xi/stereo/post/ and
http://www.sound-in-motion.com/installs/bmw_330xi.html
and of course lots of other little things (such as euro parts

)
Hth,
- Jan