The Torco Accelerator is probably one of the most complete octane boosters on this list. It has been around since 1948, and its antifragility is remarkable, probably due to its ability to customise the blend as per your requirements. While it has seen a lot of use in racing circuits, it can be used by practically anyone.
It is truly exceptional at hitting octane ratings up to 100, if not 105. Not only that, even its efficiency can be customized if you are looking at octane ratings sub-100.
A perceptible improvement in horsepower generation is also evident. That being said, it may not be as effective in older engines and is recommended for use on newer engines for maximum results. It really is a designer octane booster.