Jay,
That is a tough one, about like which is the best scope, barrel, action, stock, mounts, boots, target design or gunsmith.
I believe that the answer to your question is determined by your particular rifle. We have some rifles that prefer J4's (believe Wyo is that way also) whereas some shoot Matchkings or Bergers or A-Max. I have gone to the bottom line, whatever match bullets I can get the cheapest so that I can shoot more - as in steel plinking.
You would need a huge sample of rifles shooting a huge sample of ammo to figure that one out - by the time you did someone will have a new bullet out that claims to be better.
Year in and year out, the Sierra Matchking is just plain amazing. Matchkings seem to be taking a beating from some serious shooters here re quality control, but I believe they still set the standard to match or beat for factory match produced bullets.
Seems that the spread between match and hunting grade bullets is shrinking, the factories are making some amazingly accurate hunting bullets these days.
I am heading out shortly for a LR shoot this morning - don't really care which bullet as long as it hits them **** plates.