>>14491448Super training ultimately takes longer, but also requires less book-keeping (You can just select "Train Attack EVs" instead of figuring out which pokemon gives attack EVs, making sure you're holding the right training item and going to town). Either way, you can check your EVs in the Super Training EV checker whenever you want.
ALSO remember not to EV train with the EXP all on. OR Do, if your team is full of pokermans who need Attack EVs.