2 door for looks, 4 door for practicality.
I like the RX-8 suicide door set-up as a compromise. The downsides are that you have to open the front door to open the corresponding rear door, and the access isn't quite as good as most 4-doors.
Open:
http://www.canadiandriver.com/roadte.../04rx-8_13.jpg
Closed:
http://www.rx8media.com/displayimage.php?album=25&pos=7