[Hainland]

You are wrong Nick.

First and foremost, the breed test in the ARV has remained and still remains the old style (IMO, more of a character test) of breed test. It is not the fault of the ARV, that people did not train that way. It sure did not affect all dogs.
As for the board, you are only slightly off base. The ARV is run by one person and one person only. This is known by most. The USRC has an elected board and seems to use it's clicks to run things, but "hey" at least you have an appearance of ..........and a means to rectify.

Back to the question at hand. Both clubs strive for working and conformation Rottweilers.
Differences:
ARV uses FCI judges (along with judges from their own program). Truth about the ADRK's refusal to judge ARV events is the fact that ARV did not want to give up their usage of retired ADRK judges. The current ADRK would not have this.
USRC uses all FCI judges, including ADRK judges and their own judges.
USRC can and does conduct Schutzhund trials through it's AWDF affiliation. ARV can not.
Show results are not recognized by anyone other than either host (National) club.
ARV's breed test include a Basic Breed Test (BBT), it is very similiar to the "mental" test used in Holland and Sweden. As stated above, the Ztp and Koerung are the original style of test.
The USRC has adopted the same test as the ADRK. Changing along with the pressures of government.

Conformation shows:
It is mandatory that the winner of a USRC Sieger show is a current member and the dog must have a working title and recognized breed test. This is not so for the Select shows or titles.
ARV allows dogs with a BBT minimal to win it's Regional/National Sieger shows. Regular Sieger shows are conducted more like a Sieger show everywhere else in the world.

IMHO. There are pros and cons to both. I show to the judges that I want an opinion from. It's about that simple. I may travel across the ocean (obviously not an ARV or USRC show), if I want that judge's opinion. I do like having a voice (or at least the appearance of) for paying my dues.

I'm sure I have forgotten something..............just wanted to clarify Nick's post.