I have a quart bottle of Step 2 I just bought for refinishing my IQ Tour Pearl and Fusion. You can't buy the product in smaller quantities.
I have a chance to pick up a Radical Yeti Uncaged on the cheap, and it's finished with Royal Compound. I'm just going by product descriptions, but Royal Compound says it's 2500 grit, while Step 2 says 320/1500. On the surface, it's seems like Step 2 is a more aggressive compound. It almost looks like I'd have to progress to Step 3 (1500/2500) if I wanted to replicate Royal Compound results within the Storm family.
Ultimately, I could just buy the 6oz bottle of Royal Compound, but I'm curious about the true equivalencies.