Consumer Reports hit the nail on the head when they rated the M35 their #1 mid-size luxury/sport car. Bought a 2009 M35 w/ Nav & Tech pkg in Feb 2010 after my 2005 Honda Accord was destroyed by a fallen tree. Owned: one year. Never a problem. Great handling, pickup, & very reliable. Guess it helps to keep up with maintenance. Radio & 6-disc CD player was adequate for me. Nav, easy to operate once I learned it. Decided to trade because of lousy fuel mileage (17-18 mpg), wanted lower pymts, & a smaller car. Bought 2005 BMW 330i sedan - very satisfied so far. If Infiniti would spend more time improving gas mileage and less time designing needless gadgets this car would fly out of dealerships.
I bought a used M35X from the dealer last month. It had 18,000 miles on it and was a rental car in its previous life. I have had the car for about 1 month now. The car drives really well. The acceleration is very good. The interior is spacious and well designed. This car has the Premium Technology package and is full of cool features. It is the top pick in the Consumer Reports evaluation for mid-size luxury cars. Reliability is next only to the Lexus LS 430 according to Consumer Reports. The only issue is with the Rear Crash ratings from IIHS which is "Poor" compared to an Acura RL which is rated Good on all the tests. The Road Noise can be lower although the engine hum is enjoyable.
I just traded a 2006 M45, which I loved, for this car. I got the M35 to save a few bucks and get better gas mileage. The M35 with the 7 speed is almost as quick as the M45. The car rides great and is fun to drive, I got the Tech and Advanced Tech with Sport Packages. Love the DVD player, new 7 speed transmission with sport mode, hard disk music box, IPOD hook up, navigation and touch screen. All but the DVD and navigation are new features my 2006 did not have. I got the Blue Slate with black interior and it looks great!
I really love the 2009 M35-S. My previous car was a 2007 M35 Sport as well. The car handles extremely well, can excel quickly from a dead stop, and is very sporty inside and out. Even when taking the car in for service at the dealership, they tend to give M owners a little extra attention and they go out of their way to make you feel special. All in all, I'd recommend the M35 S to anyone.