Is mixed headstamp brass a wise buy?
Depends on the price and as others have said, what you're using it for. Last lot of 1000 once fired .45ACP brass I bought I sorted when I got it. All but 90 of them were either Federal, Winchester or Remington. Out of that 50 some were Starline with the other 30 some a Duke's Mixture. For $7 a hundred delivered(cleaned, sized and deprimed) I thought it was a wise buy. Similar experience with the last lot of 500 .38 Specials I bought. If you buy from a reputable source you shouldn't have a problem. If you're loading hunting loads for a magnum handgun, or rounds for competition, I'd definitely sort by headstamp. If you're loading range rounds not so much.