umm... 6 strings Vs. 4. Standard tuning. 6 strings will always put more strain on the neck than 4. If you have a 6 string guitar with a tremolo and you break a string, you go out of tuning.... proof that less strings puts less stress on the neck.
research what Flea plays in the RHCP. its a 4 string.
research what less claypool plays.
if there was a clear advantage of having more than 4 strings on a bass, I think more ppl would play them. 5 strings are good. 6 is overboard, adds weight, makes the neck thicker and fatter, then you gotta buy special string packs at a higher cost.
I'm sorry, Do get it if you like it, but I'm just not sold on the idea that 6 st bass is necessary.