How about on a dark red metallic color? Would you use S100 or #26? I'm going to be buying on or the other in a few days here to try out. I have NXT on the car right now, and want to try something different.
I would always use S100 over #26. However, I think that Souveran if you want to spend that much (Autogoek has $10 off) is the absolute best, wettest look on dark cars.
I've been using #26 on my dark red metallic, and I must say that it gives a warm glow and wet appearance. IMO, it brings out the "red" more and darkens the paint a bit.