Crooked Creek hit the process difference correctly. I've been told the same thing by the makers and seen it written out elsewhere. These are just primers made by their most experienced people. Sometimes that pays dividends, but sometimes you get a new guy being extra careful to prove himself who winds up turning out the better ones, or you get an experienced person who had a bad night or is so bored they can't work up to their potential. Only shooting tells you for sure. I've seen more than one table put up by someone for whom the match primers did worse than standard. You just have to try them and see what they do for your loads. By buying them, you are probably playing the odds, as it is more likely the experienced folk will do better. It just isn't guaranteed to be so every time.