I would say you're gonna get about a 45-50% yield from pork butts after pulling, taking out fat, etc..so if you think about it like this, 10 lbs of uncooked pork butt is gonna give you about 5-5.5 lbs of cooked meat. I always figure about .25 lbs per sandwich (which is a pretty decent sized sandwich) so if you've got 25 people, and you figure .25 lbs per sandwich you're gonna need 6.25 lbs of cooked meat for each person to have a sandwich...now you're probably thinking, some people are gonna have two sandwiches, i know i would..so I would plan on having about 10-12 lbs of cooked meat (you're probably gonna have leftovers but that's not a bad thing.) all in all i'd say two 10-12 lb raw, bone in pork butts should suit you just fine. If you've never done one before make sure you do some reading up on how to prepare them correctly, also make sure that you leave yourself enough time to cook them, start saturday morning and you should be fine. hope this helps.
