Quite a bit of cosmetic wear, especially on the seats and door interiors.
Sunroof sticks, and occasionally leaks in bad weather.
Just the other day, the tires began to shake at around 60 mph, as if one was loose. I pulled over, checked the lug nuts, and all seemed fine. Hasn't happened since.
Heated seats no longer work.
Bose subwoofer "pops" with certain music.
The driver's side window motor was replaced. It acted sluggish for the first few months, but now its fine. Weird.
Driver's side door needs to be rehung. Only about 1/8" too low. Not a crisis.
This, however, is. That fancy Bose stereo has no memory. Does not remember presets on the radio on, nor what track on the CD you were listening to when you shut the car off. From what I've read, it's only a minor miswiring in the stereo itself. Some power cable not plugged in right.
The J30 handles pretty well, although I have yet to try it in snow. It's got GREAT speed from the start, critical for making merges, etc. It gets sluggish to accelerate around 60-80 mph, especially on the slightest of hills.
I get slightly better acceleration with premium fuel, but slightly better mileage with regular. Go figure. I usually get about 20 mpg, but slightly more if my girlfriend is driving it. Mostly highway travel.
The car does look pretty hot. No stupid hood or ground effect, just sleek styling. I feel very pimped out rolling around in it.
When I've taken it in for oil changes, etc., mechanics have always commented that everything looks pretty solid.
Oh, and the horn does sound a little wimpy, but no big deal.
Infinitis are known as the poor man's rich man's car, but they definitely like the high end parts. It does make a difference in performance, though.