All stats check out and the other events are the same as the rotom one, you get an item that allows you to play through the event and ultimately get the pokemon, it is pretty much the same code you get via wi-fi, it makes the game believe you received, by whatever necessary means, the code needed to be able to get that item. Pokesav probably does the same as this cheat. A hack would be use the calculator trick in which you type the national dex number of the pokemon you want.
You don't understand the difference between the in-game caught event pokemon and the EVENT pokemon that are distributed via WiFi. The Arceus caught from getting the Azure Flute is not the same as the TRU Arceus. Show off the Azure Flute one and people will laugh at you for your noobness. In their eyes, you cheated to get that because the Azure Flute distribution never took place. It is technically legit statwise and PBR will not detect it as a hacked pokemon because it doesn't go out of bounds of what it should be, however, since the Azure Flute distribution never took place, the assumption is that you used a cheating device to obtain the pokemon, making it not legit. The difference between the TRU Arceus and the AR-induced Arceus is that the TRU one is allowed in tourneys and is purely legit, where the AR-induced one is not, and as far as I know, never will be.
If you are talking about the store/movie events in which pokemon are given then yes this is different, what i'm talking about is that there are no differences in getting whatever pokemon by cheats that give items that unlock in-game events and getting the same pokemon by waiting nintendo or any given store to distribute the exact same thing. i got what you're saying but i don't go to tournaments or pokemon events or even used the azure flute for that matter i only brought it up because it is easier to get these pokemon with cheats than using pokesav. if he intends to use these pokemon on tournaments and events then, for what you said, he should use pokesav.
You could just go here: http://forum.romulation.net/index.php?topic=34172.msg611394#msg611394 and download the .nds files and distribute the event pokemon via another ds/flashcart (if you have a friend or extra lying around) and just get the pokemon that way. Its easier than making your own pokesav/wondercard thing or whatever.
What if you don't have 2 DSes? You don't make your own Wondercards, you can, but you don't have to. You just download them, load them into your save, and fire up the DS and you're done.