XFKID, I happen to think the G35 is a great car. It was my car of choice before I stumbled upon the great deal I got on the Crossfire.
But my advice would be to stick with your Neon for awhile, get out from under the $4k you owe, and save up for the Challenger. (That is, if you like the way it looks). A 425 hp Hemi is going to be very enticing, and you may be glad you waited. It will be here before ya know it.
Besides, why drive a new car through the winter, if you don't have to?