Ubiquiti is a product for commercial installations, not really for your basic homeowner type. The eeros make it very easy to configure the routers / access points, and do a superb job of switching clients from AP to AP. If it were me I would run plain old Ethernet cable (6e or whatever the current type is) in PVC pipe. 50 meters isn't that long in terms of Ethernet, and then you don't have to worry about line of sight or whether the problem is with your bridge or access point. Of course, you do have to worry about someone taking an ax to your cable or running it over, but that tends to be a lot easier to diagnose. Walk along your conduit and look for a hole. Not that point-to-point wireless can't be reliable as well, but the hardline is simpler in a lot of ways.