Most of the fish I have right now, I've always wanted just never had until recently. Considering how common oscars are, I'm a little surprised I waited over 13 years to get my first one, but I'm really glad I did. He ate from my hand the first day in the tank, and even got my sev out and about instead of hiding.
I can't really think of a fish (well, other than some of the freakish hybrids and dyed/mutilated varieties) I really wouldn't want to keep