I completely disagree with Nick & co.? (I rarely disagree with his movie e-opinions.com) Back to the Future Part III is the best of the series (definitely it is slightly better than one of the best bond films, Goldfinger)
The Godfather: Part III-- I'm not that big a fan of part III, but the third time around was too much for even Sellers, as I was tired of the whole bumbling bit.