Well, I am no expert, just some one who lives and breaths cephalopods 24/7 lol. But I will be going on a expedition to Costa Rica In June to study,inventory and discover octopuses there and help the Costa Rican government establish a idea of species populations for conservation.
Now as far as octos go. A bimac is your best bet for a octo. They stay in the tank more than most, are active, and don't grow too big. They also can tolerate looser water conditions. But still require more care than fish. I stress you must prepare for months to be ready for a octo!
I never had a joubini. But I can tell you most of the O.joubinis are O.meratoris from my understanding. Joubini is a deep water octo. Not accesed by collectors often. Mecatoris is a shallow water species that can be net collected. But both are prone to escape,and are quite shy.