There really is no issue if you transport a Pakayak on a kayak roof rack. They are designed to hold the unique shape of a kayak without deforming it. I would only suggest that you follow the same general guidelines as you should when transporting any kayak: Make sure it is properly secured and not deforming the kayak; make sure the cockpit is turned down or covered so water cannot fill the cockpit; make sure the hatch covers are on tight to prevent water from filling the storage compartments; and don’t leave it sitting in extremely hot summer sun for long periods with straps holding it down.