I, too, like the lighter weight of the BBs, but I generally use the glass carboys as the extra weight doesn't bother me too much. However, the original question hasn't really been addressed and is one I am interested in too: Is there a reason not to use BBs instead of glass carboys? I think I have read either in some kit instructions or elsewhere, that bulk aging should only be done in glass carboys and not in BBs, but no reason was given. Is it because glass bottles are known to be 'safe' containers for wine to age wine, and the jury is still out on plastic BBs? Out of concern that there is a certain but unidentified benefit to glass vs. plastic carboys, I have stuck with the glass carboys but would be glad to be enlightened.
Bart Reeder
Dallas, TX