After obtaining a Pokémon with 510 EVs - it doesn't have to be from Super Training - you can also do some extra Super Secret Training courses.
While they won't provide any increases to your EVs (remember, max-EV Pokémon), they do provide items, especially if you do well!
Be aware that the "Time to Beat" stats here account for the occasional need to beat multiple balloons, and thusly the slight time boost given to you.
Note : To unlock the secret courses, you will have to acknowledge the Pokémon's maxed EVs by tapping the flashing muscly-man thing in the top-left corner of the S.T. graph, but only the first time you unlock these.