Visa 190 kami, pero we opted to stay on SA for the 2 years. We do know others who moved into Vic after a few months. Moral obligation siya, so its not really illegal to move into other states. For us, we decided to stay, as a thank you for SA for sponsoring the new chapter of our lives. Btw, I think SA is so underrated. It's a fun state to be in. Specially now that other states are going and out of lockdowns..
Back to topic, with visa 491, i think requirement magstay for 2 years for PR processing. So, depends on your visa condition, and thread carefully. If you get sponsored by a state, you were probably meant to be there...