Two favorites - a 1988 regional production of Philadelphia, Here I Come!, where, unusually, both Gar Public and Gar Private were excellent (usually Gar Private walks away with the show, being a showier role).
2005, during a visit to London, the rest of my group chose one evening to see Jerry Springer the Opera, but I picked up cheap tickets at Leicester Square for The Home Place, starring Tom Courtenay at the Comedy (now the Harold Pinter). It was exactly the kind of play and production that's done so excellently in the UK and so poorly in NYC. A moving, intimate, fulfilling evening.