My personal opinion is they are not worth the expense for a street truck strictly in terms of performance gains. They might run a bit cooler, but unless you're on a track I doubt you've experienced brake fade with the standard rotors. You would notice more stopping power with a quality set of pads. They shed water better than a solid rotor, but nearly every car on the road has non-drilled brakes and everyone seems to be stopping just fine.
All that aside, with the right wheels they look awesome! If you're running some aftermarket rims that show a lot the rotor area, and you have some extra cash laying around, then go for it.