Bengals are definitely not couch potatos. Mine once lept off of the top of my TV knocking it to the floor! But I’ve read that Savannahs are actually very docile cats. Plus, considering how expensive they are I don’t think too many owners would wind up abandoning them.
I still think the largest breed of cat was Sammy Davis Jr.
I’m surprised at the numbers on the maine coon cat. Mine weighed as much as 27 pounds, although she declined to 22 lbs in the last years of her life, and while she wasn’t exactly the runt of the litter, she wasn’t the largest. Wonderful disposition. One of only two cats I’ve had that came when called, and responded to her name. Long body, long tail, lotsa fur. They also tend to be long-lived cats (or getting the most bang for their nine).