Titanium dei is the best I've used. It doesn't discolor or get brittle with age/use. As with any exhaust wrap, it will hold in moisture, so if your going over bare metal, some sort of high temp paint should be used first.
I used DEI wrap on the crossover on my supercharged Pontiac and it worked great. The crossover was near the supercharger and the wrap lowered the intake air temp. a bit. If I remember it was a kit that came with a high temp clear coat that I sprayed on the wrap. Never had any issues.