I did some searching to see if there were any musical preference tests that I hadn't already taken, and stumbled upon this one:
Music Psychometrics
Why do I think it's so bad? Well out of the 58 samples, there were only two or three that I remotely liked, and my results were all like 80-95 for every category, well below the average of 100 for all of them. I don't know if it's just that 90% of the samples sound recent (and I don't like current the current music production value), if it's down to how short the clips are, or if the samples are actually a bad selection, but still, it's pretty bad. Strangely most of the users on another forum scored high in some categories, so perhaps it's just me with my strange perception of things...