As somebody said above, generally, the only people who can tell the difference are other bass players and the various tests at Bass Bashes I've attended suggests that even we don't do that well on this front.
Maybe there is some placebo effect when we play something we gel with - if that's the case with an expensive, vintage instrument then go for it. Many can get the same from low end instruments - I swear that the easiest basses to play I own are my Bass Collection Nanyos. Love the necks, love the tonal palette - makes me enjoy playing more - I think I play better..
A friend of mine did a blind fold test of Gibson LP style guitars and ended up buying the cheapest (which he preferred most).
I used to take new purchases to a friend's for his opinion - he rarely liked them - he always preferred his own MM Ray - I couldn't get it, I felt it was "ordinary". Clearly what suits one, doesn't suit another.
ATEOTD the instrument only has to please ONE person - the person playing it!!