"Compared with experiencers whose decisions were escapable, those who were not allowed to change their minds showed a greater preference for their chosen photo two and nine days after they had made their decision."
So being able to swap your art may actually make you unhappier in the end! But it also mentions that people think they'll be happier given the choice, and will pay good money for it.
[0] http://www.apa.org/monitor/oct01/strength.aspx , under the "The price of freedom" heading