Manual trans is mandatory. This car can't just be fast. It must handle well and be sporty. Think of a faster more luxurious version of the SVT contour. My cousin had a Lincoln LS. It was nice, but not enough "sport." And the manunatic auto shifting sucked a lot.
THe G35 interior felt a little cheap, but was much better than my ford and better than the 350Z.
Price range is max 50k. Preferably closer to 40K.