For years I only had one bass and it had 2 vols. After that I had basses that were 1 vol for a few years and then just recently picked up a v/v/t Jazz. So I've had quite a few years with both styles. I don't mind the single vol/balance approach but I will say that if I had a choice that I prefer having independent volume control for each pickup. Why? Honestly I have no idea; it's not like one way gets you tones that the other way can't or vice-versa.
I think I probably prefer vol/vol to vol/bal just because I spent so many years with only one bass and it was a vol/vol. Go with what you're comfortable with.
EDIT: Yes, as said above the nice thing about vol/bal is that you can turn down without changing your mix. However if you use a volume pedal or tuner mute etc then this may be a non-issue.