I dont know if you have kept them for any amount of time but i have 2... 18" and 20" that r now just over 1 yr old and i have to disagree with u because out of every fish i have ever kept they by far have the most amazing personalities and intelligence i have seen in fish.. if u pay attention to them u will discover they all have their own personality... can be trained and taught all sorts of things and they even enjoy being patted and can get insanely jealous if u show attention towards another fish... or cat in front of them

even splash u when they r cranky at u. Can be taught to reconise differant colour/shaped nets as 1 for feeding.. 1 for removing things etc.. can be hand fed... And if you dont pay attention to them they will sit in the corner or hiding place and sulk.
Big growth rate, big appetite, big mess, big attitude and a big personality to go with!