I saw that you've already made your decision, so congratulations on that!

I did want to add my opinion, though... just for argument's sake.

I've owned both and prefer the RX-8. I had an FD for 4 years and have had my RX-8 for just over a year now.

The FD is an amazing sports car and racing it was an absolute blast but the RX-8 just provides so much more from an all-around point of view. The FD can be faster, but that doesn't mean it is (especially in the hands of most drivers) . The RX-8 is more likely to be faster more consistently, it's more fun and less hassle.