From my point of view, I always want to achieve the absolutely best sound quality possible within my financial means. That always means only owning one. So, I would say, sell them all and purchase a better amp.
But beyond that….which sounds best to you? I could not possibly help, since I don’t have your values, system and venue. If you can’t tell the difference, then either just randomly keep one, and figure out the weak points in your system and use proceeds of selling amps to improve the systems overall sound.
Or maybe sound quality is not the top priority to you and someone else will suggest a strategy you like.