Maybe Fischer would be best at Fischer Random...

Although it is to be expected that the top "regular" chess players will also be the best at chess960, it is kind of interesting that Nakamura's record against Aronion is 0-5-1 (not including blitz per Wiki), while he thoroughly crushed Aronian in Chess960 in the 2009 championship. 

Was Fischer correct in that opening prep has really ru-eened "reg'lar" chess at the top levels and therefore chess960 (or some other variant not requiring memorization?) is the way to go?

I still have to go with the Cuban, simply because he was not much into openings anyway and still fared quite well at chess in his day.  Tal and his craziness would be intriguing.  

Thank you for putting the image of Tal playing 960 in my head - awesome.