I've rehashed the lot right before going, and stopped in the middle of 2, because it was wrecking the experience for me and started to lose enthusiasm for the Force Awakening.
I say this as a hardcore SW fan, 4-6 now look and feel very dated now, mainly due to inconsistent ropey in-game quality CGI added by Lucas to the old VFX, but also there is something about acting, amplified by several frame conversions and pitch shifting between digital releases, the amount of over exaggeration and almost cheese puts a nice childhood patina on it - yet it bridges perfectly with Force Awakening, despite the fact, that morning after seeing it I feel like I've seen more of a Star Trek bridge to Star Wars universe reboot than fresh SW idea. Don't worry about internet moaning - 95% of it really isn't bad movie - the moaning is about 30 years of ballast that no screen writer and director can deliver these days, not unless they lived every page of SW universe ever since, and there are no such people in Hollywood, even Lucas himself couldn't deliver for fans.