i've had the experience owning the following cars since 2000 (all purchased new):-
00 jetta VR6 / 02 Acura RSX / 03 nissan 350z / 04 Focus zx3 / 06 mazda3
i'll get rid of the mazda 3i probably next month. The only car i'm keeping is the nissanZ. i hope this will give you an idea choosing the right car minus the headaches.

 

What happened to your Mazda 3i?

 

the 06 mazda3i manual tran i bought in May with only 1700miles developed a whine/ hum/buzz at 80mph but the the dealers refused to look into it cuz they wouldn't be able to drive over the speed limit in order to duplicate the noise. i think a reputable auto manufacturer would and should deligently jump into the chance to investigate and to eliminate any possible defects/ bugs with a brand new car. nuf said...time to move on.