My advice if you do get a second copy is to be sure you have time to dedicate to both towns, especially if you worry about villagers you like moving out. I have 3 copies and I found I was dedicating 5+ hours a day to make sure I didn't lose anyone on them and it became a chore and tiring. I put one of the towns on indefinite hiatus because of it.
I'm not trying to scare you off from it, it's just my experience. I think 2 towns is manageable, and I'm less stressed worrying about villagers moving out and stuff. It IS fun though to have 10 different villagers and different towns to work with.