Has anyone had any luck, or even tried to use a 3 gallon keg for 2.5 gallon batches with the Z? I want to ferment and serve out of 2.5g kegs, I simply don't want a 5g keg around that I won't be using (nor do I want to mess with transferring out of the 5g to the 2.5g after the brew). Plenty of...