I know some people are using it intensively in a club in Geneva. They have a powerful PC that gathers NDI from artists laptop and use MadMapper to map all this content to a bunch of video projectors.
The problem is encoding. NDI will use your GPU to encode H264 streams. It does it fine, but encore 10x fullHD, I'm not sure. Since MadMapper you can force the engine to run at 30FPS, so 10 1080p30 would be equivalent to encoding 5x 1080p60 streams. With a good GPU I think that could be ok.
To test, I would suggest installing MadMapper on another computer, even demo version, and display all the streams you get from the other machine. You could also use several instances of NDI Monitor.
Let us know your findings !