Bauer II, I'd only consume BCAA's as part of an essential amino acid mix. Since they can be anabolic and anticatabolic, you'll want to maximize this effect by supplying the raw materials from which to make muscle protein.
Another way of looking at it; you can supply the stimulus for muscle growth (ie the BCAA's), but unless you supply the raw material (protein or EAA's) you won't build more muscle.
I prefer powder form to mix in with my Pre-PWO drinks (plug for Surge anyone?).
A dose of 10g would be efficacious and cost effective. Using less will have an effect, albeit smaller than a higher dose (makes sense I guess).
Formulations containing other amino acids are said to be "Branched Chain enriched". As always, be sure to get a full complement of essential aa's with your BCAA's.
Keep in mind that I have yet to see a benefit of either valine or isoleucine.