To expand on Anachronism's post:
The only difference between standard and match/benchrest primers of the same number (such as CCI 200 and CCI BR2) is that the match/benchrest is made more consistently. There is no difference in brisance.
You will hear almost anything about match/benchrest primers, including that they're hotter, or cooler, or the cup is more scientifically made. But I have visited the factories and the only difference is that some workers are better at spreading the priming mixture more evenly, and those are the people that get assigned to make CCI BR's or Federal M's. Otherwise they are identical to CCI 200's or "regular" Federals.
The entry is copied from the 24HourCampfire site, and was written by John Barsness aka Mule Deer.