Usually the difference is a bucnh of $$$$.We have reman masters on 4 old Mopars.All from Advanced.Mine is at least 15 years old.No problems.We used quite a few at work also.I think in 30 years Ive had maybe 2 or 3 bad ones.Most people that have problems over pushing the guts when bench bleeding and or bleeding the system.Push too far and you risk tearing the seals inside.Rocky