You know the old saying goes, find a pit that you think is the size you want and need for your type and style of cooking, then buy the next size bigger.
I like the dry cooking technique of the vault . Different shelves have different cooking results. The top rack IMO is best suited for chicken. It browns the skin alot better from the malliard reaction. Bottom rack can be foiled to catch drippings to make a really dry environment if you want good bark formation. Keeps the juices from hitting the bottom drip pan. So many ways to cook with the vault. I still think a UDS cooks a better chicken from the direct coals. Never was a big smoked chicken fan, I like it BBQ'd and apparently the judges concur.