[isflojo]

I own a black IS-F as well, and it was the best color choice for me. I had a full clear bra (covers everything in front) installed on mine and you can hardly notice it. In addition to the products mentioned, I suggest that you use a duster prior to quick detailing to get rid of particles that might cause light scratches or swirls.
As far as investment is concerned, I'm very satisfied with the performance and quality of the car. Just look at the reviews of Lexus and you'll feel good about your investment. It's the reason why I didn't go European.