pRo had many server perfomance issues(look official fb-page for the proofs).
mysgRo same problem. btw, msygRo is with pRo(+thRo) in the same adminstators. Therefore is mysgRo a official server.
I think, the pRo-community is careful. Because of their old-closed server.
The other big topic is ro:zero. But i cant write many things about that. A Vmod will delete/edit my post(maybe).