I've cooked various standing rib roast sizes over the last couple of years (~4, 8, 12 lbs). This Christmas, we have the largest number of people coming to dinner : 18 (so far).

I've been debating about whether to purchase the whole 7 bone standing rib roast or to ask for 2 roasts from the loin end, described as the most tender and flavorful section. We aren't going for "prime" grade; these are "choice" grade roasts. Your thoughts, opinions on this are much appreciated!