The cabin is absolutely luxurious, with a very sporty feel. All of the materials feel wonderful (I got the Premium and Deluxe Touring packages, which add a little to the experience). It is whisper quiet, has LOADS of power, and an amazing array of gizmos. In searching, I ended up visiting dealerships in two different states, and they were both really great. I bought it at Cochran Infiniti in Pittsburgh, and they include a pick-up service where they'll drop off a loaner Infiniti and take your car to service (even though we live 80 miles away!).
Power, ride quality, stereo, feel of interior materials, exterior design
I wrote this review and have some updates (I recently traded in the M for a 2012 Audi A8). So here are the parts that got to me over time:
- The cabin is NOT whisper quiet. It's actually pretty loud. The upgraded Bose 16-speaker stereo is supposed to do something about the noise, but it doesn't. At all. It's a LOT louder than I was hoping for. Edmunds found the interior noize level at 68.7dB (here: http://www.edmunds.com/infiniti/m37/2011/road-test-specs2.html). That's higher than the BMW 535i at 67dB and the MB E550 at 66.9dB (couldn't find info for the E350), and even the E350 CONVERTIBLE at 67.1dB).
- For all of its technology, it didn't ever surprise me with an "Ohhh, it does THAT" experience. It does what it does, and it just didn't feel as advanced as I was hoping. Granted, I didn't get the Technology Package (adaptive cruise control, lane assist, etc.) because all of the reviews stated that these systems were really intrusive. But maybe I would have been more impressed if I had gotten that package.
- It's only got a rear camera, tho it's got a LOOOONG hood. That hood is sexy as anything IMO, but it needs to have a front camera or at least front sensors.
- The trunk feels really cheap. I don't know why, but it didn't actually close more than half the time. I would have liked to have a power open/close option.
- The nav screen could be bigger. There's room for it (at least an inch on each side is just black plastic), so it looks like someone decided to go with a smaller screen.
- The sound and the power. They're just GREAT!
- The interior design and materials are beautiful.
- The seats are comfortable as anything. The upgraded semi-aniline leather is really nice.
My new opinion:
Buy one used and you'll be happy as a clam if you want a fairly luxurious SPORTY sedan. If your main goal is luxury or technology, I think you should look elsewhere. For example, the BMW 5 series offers a heads up display, night vision and power close doors and trunk, along with internet connectivity. None of those are available in the M.