Well, from personal experience, I am 33 years old, Im a professional mechanic, Ive owned 10 different vehicles, and only one Japenese. That would be my latest vehicle, a 96' Isuzu Rodeo/Honda passport.
I can say without a doubt in my mind after owning this import brand that Jap. quality is far superior to american. Just looking at the attention to detail and engineering is something you wont find in an american make.
I think there are the obvious remarks..."anything mechanical needs maintenance"...well....duh.
Its no secret that Jap. cars are OVERALL of superior quality. This has been well known and talked about for many years now, and there are statistics to back it up.
As for Ford, Ive lost a lot of faith recently. The mustang in particular has been a fairly reliable and well built car since the fox body, primarily because of two excellent engines, the 302 and the 2.3 are both known to be reliable, long lasting engines. (althought he 2.3 will probably require more maintenance when higher up in mileage). The basic platform (the old fairlane suspension) is simple design and reliable. However, these cars flex like crazy and arent very strong structurally without the aid of sub frame connectors.
I think we can all agree that american cars were of good quality back in the 60's and early 70's. Maybe they were even better in the 50's, but Im not that old to know from personal experience(maybe some old timers can throw in their .02). Around 1975, pollution controls became mandated with stricter emission regulations (first year for catalytic converters) and american car companys started playing with electronic igniton for the first time. In these years, all the way into the through the 80's american cars were garbage, period. I think GM was the worst in this time frame, Fords werent that bad, and most of us remember chyslers srtuggles with bankruptcy. This time period is why I hate GM cars to this day. I saw so much crap from GM it was apparent to me that they just didnt care about quality at all. Fords were better, but didnt compare to the quality of the Japenese cars.
Since the late 80's into today, american cars improved greatly, but it was this period from mid 70's to mid 80's that damaged their reputation the worst, and when people starting buying Jap cars because of their reliability along with the feul crisis.
As far as power, yes, most of them are underpowered, and yes, I agree that this can help reliability (toyota in particular has made some extremely reliable but extremely underpowered pick-up trucks in their past), althought he high powered jap cars are just as reliable as the underpowered ones. They dont take shortcuts. My friends 300ZX has a main bearing support girdle from the factory for example.
Ok, ive rambled long enough. Bottom line, American cars have improved, but still take a back seat to Jap cars in quality.
But if you like rear wheel drive v8's like me, youll keep that stang around...
And my 96 Rodeo makes 190 horsepower from a N/A 193 cubic inch engine. Not bad.