they are more well known ...and make good kits but the stage 6 modular and sport pro are made by athena
good explanation theyre rox boy and the athena kit will eventually become just as popular just people hear good things about stage 6 ones but how do you know inless you try ehh?
There's quite a few parts with different names which are basically the same. My crank is a Top Racing brand it is made by a company called Jasil, they also make the Doppler crank. The only difference is the Doppler has a smooth finish and the Top Racing has a rough finish which apparently helps combustion.