In my opinion, if the M2 OR2800 Antenna Positioner has one weakness, it's in its lack of a weather-hood. The main shaft extends out of the top of the positioner case where the mast plate attaches to it. The bearing set that the main shaft is centered-in is directly exposed to rain and the elements. Water coming to rest on top the bearing set has few choices but to either evaporate or to penetrate through the bearing set and into the positioner housing.
Click on any one of the series of pictures below to step-through enlarged versions.