The problem is more that you need a huge tank and lots LOTS of current and cool temps (chiller) and really clean water to keep them. They suddenly dont become worth the effort, IMO. They are awesome fish, but not so good to aquariums. Oh, and they do get really ugly when they get big, which is too bad.
They do taste good though, lol. This last weekend i caught about 40 trout out of a "gold metal" (artificial fly and lure only w/ different restrictions on what you can keep) lake near Leadville, CO. I let them all go except for one, which I had for dinner

. This lake is the bomb. None of them were under 12 inches in length and the largest was a hair over 20 inches in length and weighed about 2 pounds (doesnt sound big, but its big for a trout in most rivers/lakes in CO). And it seems like they bite pretty well all day long.