I just bought a 2018 Roush Stage 2 earlier this week. It's Royal Crimson with Roushcharger that was added by the dealership (I assume before it was sold new). I've done quite a bit of looking and haven't been able to find if there is any sort of listing or breakdown of production numbers for '18. From the research I've done, it looks like 2018 was an interesting year, with no Stage 3 and the beginning of the Jackhammer. Was there ever a Roush installed supercharger done in 2018? From what I could tell, even with the Jackhammer it was a dealer installed option. The one I bought sat unsold until last Spring and then was traded in this winter. It's currently got only about 5000 miles on it, but it'll climb relatively quickly. Gotta say I'm having a blast with it. Going from my 315hp '08 Bullitt to a 700hp '18 RS2 is a pretty dramatic leap in horsepower.