It's my first car. Bought it new in August 2002. Have been driving it ever since then and no real problems occured. If I have to be really picky, then here are some minor issues: (1) twice in winter morning, with temperature at around minus 20 celsius (I live in Toronto), the stereo stopped functioning --- the problem disappeared next day. (2) experiences over snowy roads is not as good, especially when making turns, the car could slide sideways. (3) My girl friend complained that air circulation is restrained in certain modes; from reading the reviews here that seems to be a common complain, but it didn't bother me that much. Overall, the car has been fun to drive and reliable.
The exterior design. I like the look of Proteges better than the newer Mazda 3.
More horepower out of 2.0 L -- that seems has been done in Mazda 3. More powerful air conditioner. Better fuel economy.