The brand I've had great results with is Solaray. They make all kinds of complexes and in such a way as you can moderate dosage at will. I tend to keep things simple and get their "Spectro" mixture of all kinds of vits, mins and herbs, but they do have B complexes too.
The only good liquid vitamins I've found - a great zinc one - was through my chiropractor. something-genics? argh can't remember the name argh. they don't sell to stores, only to practitioners.