I just got a 50 amp esc so I'm all set to do 4s with my rimfire! Currently the only prop I have for the edge is the 12x3.8 and it runs on the hot side, so i'm not gonna throw a 4s in it till I get a new prop. It really doesn't need 4s though. I'm thinking about building
@Grifflyer 's hotliner as a 4s speed monster. I even got a 12x12 prop for it that I'll trim to a 9 inch for some extreme 150 mph fun!