If you spend a lot of time searching the web for octane booster test results, you may come to the same conclusion I did, which is that most of the stuff sold is junk.

The ones that do work (and I'm not even sure which ones those are right now, since formulations change and what worked 5 years ago might just be more junk now) don't make a huge improvement. But they'd be good enough for some margin of safety if you're running on the edge. But all that hype about turning pump gas into race gas is total b.s.