No regrets as yet but then again I haven't got my car yet
I think any upgrade to the rcd310 is essential for looks alone and the 18 inch alloys
One slight regret is the lux pack as folding mirrors don't work on the key fob, but hey it was cheap.
Other regrets would be (if I ordered them) the leather(the cloth is more special), sat nav (just too expensive) and heated seats (no need in london).