I began using clay on my cars a few years ago. If you run your hand across the surface before and after using the clay, you should notice a difference. I guess it depends if you have a garage and actually use it to park in. If your CX-5 sits outside the paint will collect more microcontaminates...
Sound is always so subjective.
I have had a lot of aftermarket systems over the years yet I think that the Bose system is a very good choice. The bass does not go down to subwoofer levels and this is a very good thing for me personally. Unless they are set up just right, I find most subwoofers...
I thought Subaru sales were way up? Something like 30% over last year?
I also looked at the Forester 2.0 turbo and loved almost everything about it. It just didnt have the upscale interior like the CX-5 Touring, so the Mazda won.