Choosing rootstocks for your apple trees

[@tarachand7935]

great information

[@garettanderson6772]

I want to grow the biggest apple I can. I live in zone 8 in the USA. I was thinking I might purchase some Hokuta scion wood and try to graft it to a rootstock. This will be my first try. Do you know if one Geneva rootstock is better than any of the other Geneva rootstocks as far as size of the fruit goes? Are they all capable of growing the same size apple if grown correctly? I also want to grow the blackest apple possible for a hobby grower. Do you know of any scion wood that grows extra black apples? I want to grow the Black Diamond but can't find a scion wood source. Thanks in advance.