I leave it out.... I leave it in...does not seem to make any difference on mine. The point about the potential of bugs or other getting in while the swlide is out, I would say that is good case of an owner needing to keep up with constant attention to these kinds of things, and fix or modify any seals that could allow for that type of incursion. Good practice to take a good close look at all the seals all the way round, very regularly. My trailer has double seals around it when the bumpout is open and triple seals when the swlide is closed.