This will most likely stir some up, but IMHO most average AR shooters (not comp guys) do not honestly shoot and evaluate each particular brand. They go by heresay and their buddies opinion. If most shooters have an issue they automaticly blame the ammo instead of the platform ie. dirt/carbon build up, aligned gas rings, weak extractor springs, loose bolt key, stretched buffer springs etc. Some ammo is better than others at covering up an underlying issue. Dont get me wrong, some ammo performs better than others but 95%+ of today's factory loads should run in any given AR. YMMV