I would chose the Infiniti G35x with AWD. It is a fantastic car and the new design for the 2007 models is great looking. The horsepower of 308 is unbelievable and the car handles wonderfully. My only gripe is that I wish the 2dr version of the G35 came with AWD but it doesn't. I also looked at the Lexus IS w/AWD and that car is a total dog-no pickup at all. I'm coming from an Audi A4 with a great quattro/AWD system. I would have to says that the Infiniti AWD is comprable and really will be giving the audi a run for its money. The infiniti G35x really gives you a lot lot lot for the money. No personal expereince with the acura only hearsay.