Ours on or DRV 36RSSB3 or a blessing and a curse. I think the blessings outweigh the curses but I wont really know until a few years down the road. Been full timing since Oct of 2017 and been through one Oregon fall, winter, spring and now going into summer. We had that driving, heavy, Oregon downpours, freezing rain, snow, and now 95 degree here so far.
The blessings are, the toppers do protect those slide outs from the elements, debris, and most of all, keep wind-driven water/rain away from the top slideout seals. I will gladly live with the occasional noise when it is windy, to know that the Oregon rain wont be penetrating inside that top seal.
The only curse I really can see for having them is, I can't clean and condition the top seal of the ODS slideouts. And this is why I say I have to wait for some time to go by to see if it's better with no toppers than with. Not conditioning the top seals once or 2x a year could make them fail/crack quicker and have to be replaced sooner than if I didn't have toppers to begin with.
If anyone has come up with a good way of cleaning those top seals under the toppers, please feel free to share. I would love to hear how you guys with toppers do it or don't do it for that matter.