There are two sides of competitive battling in this generation: wifi battling, and then there's Pokemon Online (there's also the other battle simulators but they don't apply right now, but I guess you can answer if you used them or not?)
Which do you use? Why do you use the one you use?
For those who prefer wifi: Why do you spend the time/hours EV training to play wifi when you could do it all on PO?
For those who prefer PO: Do you play competitive only on PO? If so, do you plan to go back to wifi battling?
If you do both, why do you still battle competitively both ways?
Discuss! Please don't answer this like it's a list, just questions to form your answer on! :(