Yeah, the way it works now for the G35 Sedan and Coupe is this:
This applies for both Sedan and Coupe models:
If you want auto, you get 280hp. If you want manual, you get 298hp.
tool fan, $37,500 is just around the price of a fully loaded G35 Sedan.
Don't go for the E320...similar (if not the same) acceleration as your 530i, but the engine doesn't sound nearly as nice.