If you have an interest in good accuracy, buy a small quantity and try it. When I first purchased an AR some years ago, I sampled about ten or more bulk ammos, shooting groups from a benchrest. They all fired and functioned perfectly but none were very accurate.

Hornady, Winchester, and Federal Match ammo (very expensive) shot quite accurately as expected. Well-developed handloads with good bullets did as well or better than match ammo.

If accuracy is unimportant, you can probably find a lot of good buys.