It works both ways for me. I hate Star Trek with a passion, particularly The Next Generation and Patrick Stewart. As such, I have a hard time getting into STTNG, even though it plays great. I hate that theme so much that it affects my ability to enjoy the machine. I recently passed up a VERY nice STTNG for a great price, just b/c I can't get over the theme.
On the other hand, I am an enormous Sopranos fan. Majorly. But that machine sucks. If there was ever a theme I would buy without regard to play, it would be Sopranos. But I wouldn't give money for that thing.