They sun oxidises the clear plastic coating, I'm pretty sure you'll find it's pretty much the same product on all of them. I've heard that tooth paste and elbow grease can bring them back, but I haven't tried it.
The only thing I'd add is, I've broken TWO aftermarket clutch cables and I think they're garbage. I ended up practically blowing the manager of a Yamaha dealership in Vernon British Columbia so that he'd sell me the one off of a new Roadstar at 5:30 on a Friday night on a long weekend (really a much longer story). Anyway the Roady cable is a HUGE!!!!!! improvement over the aftermarkets. Fatter, smoother and a lot easier on my hand. It doesn't have the bend that the Warrior cable has at the top. I highly recommend it.