It took me four years to gather enough people for an IDOLM@STER dance group. So don't say you're "jealous" until you've tried for a few years. Good luck!
It varies from person to person how long it takes to learn a dance routine. It takes me about 10 min, maybe 20 for a really hard song -- others take a few days to learn a song. We usually spend a few hours all together working out the details, and after that it's just practice, practice, practice and hope you remember everything on the big day.
Oh boy, Jupiter.... ahhhh Koi wo Hajimeyou is sooooooo Johnnys and so incredibly dorky I really wouldn't recommend it in front of a crowd with no knowledge of Jpop, unless you want to be compared to NKOTB. Alice or Guilty is a lot safer.... as long as you have the flair to pull it off.
