I have several favorite brands of ammo that I have using for years. When I get a new gun, I run a few boxes of each brand just to make sure the gun will eat it.
My criteria for ammo is that it is first, clean burning, and second, accurate...in that order. I don't care how accurate it is if it isn't clean burning I won't use it.
Further, with the expense of ammo these days, I still buy my favorite brands but look for bulk deals, using buying in 500 or 1000 round lots.