I currently do 5 gallon batches, AG and am looking to build a little brew sled for myself. For reasons of simplicity and cost I'd rather use kegs than pots for this setup but am wondering if there is a maximum size preference for this type of thing. Specifically, there has got to be minimum grain bed depth for mashing. Would a five gallon grain bill be too thin in a keg? Additionally, if I cut the top third or so of the keg off would that affect it's rigidity? Would I be better off with 1/4 barrel kegs.