Multiple RBK53 systems in parallel - do they disturb each other?

This sort of screams out for a professional WiFi installer to do a survey of the building and recommend a solution.  Some random factors:

• How big is "mid size"?
• Shape and dimensions of the building are important.
• Hotel construction often involves LOTS of concrete (at least many of the hotels I have seen under construction)  Sometimes the walls between rooms are concrete.  The more concrete, the harder WiFi is to deploy.
• Yes, assigning specific channels to the 2.4G WiFi can help reduce interference, but the 5G channels are limited.  The Orbi 5Gbackhaul channel is the same on every system.  Unless the floors are all thick concrete, there could be interference.
• Residential Orbi products are not especially easy to mount in a commercial environment (where ceiling mounts are very common).
• Residential Orbi products all require electrical power at each location. Those commercial units are almost always powered through the PoE cable connection which solves two issues at the same time: (1) not using WiFi bandwidth for backhaul to the router and (2) providing power in a concealed way.

Hotel WiFi has become an important consideration for travellers, so improving WiFi is a good idea.  The 2016 residential Orbi product may not be the best solution.