Took some wrestling to get both seats back in to place with the new covers on. I found out it works best with putting back the pillion seat first, then the rider's seat.
On my BMW R1200 GSA there is not a lot of air to flow through the mesh, but it is faintly noticeable. The seat feals firmer, and, as riding after the bike having been parked in heavy rain prooved, you can sit on the mesh without getting your bum all too wet.
Am looking forward what it can do in hot summer weather