1-) JUSTICE YELLOW IS THE CANON FANDISK. It's a direct sequel to Resurrection Supernova while EV is a spin-off (instead of being sent to remake ROMANXIA you go undercover into HoneyBuzzard IV's school).
2-) THE GAMES ARE SHORT, REALLY SHORT. About 3 hours while getting distracted by internet/poupee/other things LOL
3-) THERE ARE ONLY 4 CGS FOR EACH GUY!!!! YOU GOT TO BE KIDDING ME!!!! AND NO, THE 4 OMAKE CGS DON'T COUNT BECAUSE THEY'RE ACTUALLY 2 WITH DIFFERENT CLOTHES/POSES
That being said, if you were really desperate those guys weren't chasable in the main game, the fandisks are for you since you get all you can dream of. Else, I don't reccommend the games at all ==;
P.S. there are interviews with the seiyuu slowing coming up in the sites