T mariae were very easy to get here in the recent past, used to see individuals turned in at LFSs with aggression problems, not unlike T buttikoferi, although as Matt said, not quite as lethal.
I have kept many Tilapines over the years, and find them to be food focused, but a bit blank as far as personality goes.
But it seems to me the best way to get an anthropomorphic (or should I say dog-like) personality out of a fish, is to raise the it without any other fish in the tank, so even a Tilapine with an owner responsive bent may even be possible in that manner.
Although the long domesticated aquarium strain of oscar, is probably the best choice.
That said, I have found Tilapines far from boring.
I have 3 different Tilapine species in my tanks at the moment.
Tilapia zillii, responds to food, but hardly a bright light.

Saratherodon linnelli a C.A.R.E.S species from Lake Barombi mbo, bit skittish

And my favorite, Stomatepia pindu (also a C.A.R.E.S species) from Barombi mbu

Both the pindu and linnelli came from Matt

Others I have kept are
Tilapia bythobates, a small, colorful, feisty species from Lake Bermin

and Oreochromis tanganikia, that gets large and gets a personality slightly less Tilapinish, plays fairly well with others, and gets a very iridescent blue when mature
