https://blackrivertactical.com/WP/Ad...Drive-c6464009
I use their gas block insert rather than the tubes for one of my rifles; the other rifle has an old MicroMOA Govnah AGB, and I will probably use a Govnah on my next build.
The Superlative does sound interesting, though I've heard some mixed reviews about the efficacy of the bleed-off.