Yes they are. When we were tuning the alcohol on Dave Peters car years ago, we would take it out street racing a few nights a week. For a while, he would jump on it and it would detonate HARD. He'd say "nope, still not enough alky" and we'd add a bit more. He would do that all night for weeks at a time. That motor had over 140k miles on it when he started that project.

I'm sure an SR would make higher power with a stock bottom end for longer, but if you want 400hp at the tires and never have to worry about headgaskets or pistons the VG is very tough to beat.