Not All coin are graders the same

There is pluses and and minuses to this. I had plenty of PCGS coins that would not cross to NGC. PCGS does not see NGC as an equal,but NGC does and a few collectors in here have the same coin with PCGS and the same serial number.PCGS has plenty of PF70 grades in the 1970's and so far NGC has not found any.I currently own 577 certified coins in my registry with only 3 coins being PCGS. If PCGS would be fair across the board an let NGC in their registry, then that would be unfair. NGC should boot all PCGS coins out. PCGS coins do bring a premium but it is different company