We debated getting the chicken pox vaccine for the reasons you all have discussed and decided to go ahead and get it. One thing that helped sway me was my son's dr. explaining that the vaccine has been used for many years (I think it was used in Japan? quite a few years even before in the U.S.). His dr. said that the kids of my son's generation (14 mo.s) would have boosters available if it was found necessary. (The older kids would start showing the need for the boosters and his generation would get them automatically.)