Prime sirloin in a crock pot
I don't even braise or stew choice sirloin - too good a cut of meat for that.
I've never bought prime sirloin but I'd grind or chunk some up for some mighty good chili - chili grind of course. (I usually only use round or chuck, but at that price ....!). Also, make some chopped sirloin steaks or burgers (Alton Brown had a good recipe using a food processor I think. I'd use the grinder on my KitchenAid since I don't have a food processor).
Steaks? Roasts? Steak tartare?
I've never seen prime anything at Sam's, nor choice sirloin for that price - I'll sure be on the lookout for it. What a find.