They were all pretty bad. Some actors (Hamill, Fisher, Ford) can handle less direction than others. Lloyd & Christensen were awful. McGregor seemed better by comparison but really wasn't good. Neeson was okay. Ian McDiarmid was the best in TPM & AOTC, but had some major cringe moments in ROTS. Overall, Christopher Lee was my favorite. He would've made a good emperor (in ESB & ROTJ).