I saw them 6 times altogether - 5 with Gabriel, once without. If you want to see the nearest thing to an actual Genesis show these days, Steve Hackett's tours usually focus on a particular era, much as Nick Mason's 'Saucerful of Secrets' tours concentrated on pre-DSOTM Floyd.
Hope you enjoy the show! (Just watched The Musical Box on YouTube, at Hammersmith Odeon - they seem pretty good )