I only have a 4ft and it's staying that way for some time so I would like something that MAX get 16" inch and would stay on the smaller side.OK, I guess it depends what you consider huge.
So does that mean you are only going with captive bred Polys? I know they're typically smaller. But I think most UJs have the potential to get to 12 to 16 inches over many years. (Of course with the big 3 even bigger.)