I can't say that I've ever ridden a truly finished horse. Even the lesson ponies had gaps or shortfalls in training if you looked for them. I've seen show horses educated to a level that, should my guy ever reach that point, I would die of pride and marvel at my good fortune, but were still in training to become better. To me, there's always a little further to go in training; to get him a bit lighter, a bit rounder, a bit more collected, etc. Of course, there does come a point for most horses at which conformation becomes a factor in performing to a higher level.
What are your thoughts? Do you have criteria for a "Finished" horse? Please, if you like, post pics or video of what you consider to be a finished horse in any discipline or equestrian endeavor.