Physical size is misleading. (As is advertised square feet of coverage.) WiFi routers typically have omnidirectional antennas, which radiate a horizontal torus shaped pattern where the maximum strength is "out to the sides" and the minimum strength is "directly above and below". Suppose one Orbi gave excellent service up to 30 ft. from the unit. That would be a circle with radius 30 ft., which is 2,800 sq. ft. If the satellite is placed 30 ft. from the router and also covers 2,800 sq. ft., at least 40% of its coverage would overlap with the base router, which gives an addition of about 1,600 sq. ft. So, a total of 4,400 sq. ft. WOW.
But, wait. Suppose the base router is up against one wall of the building. Half of that 2,800 sq. ft. is covering the yard. Dang. And, suppose the base unit is pretty close to the opposite wall. More sq. ft. covering the yard. Shoot.
So, how big is the building and where is the internet modem?
Netgear advises putting the satellite close enough to the router for the LED ring light at the top to turn BLUE for two minutes when it is connected. (It goes out after that because people do not like glowing things in the dark.) For most people, that works out to be about 25-30 ft. away, depending on what the walls are made of and other obstacles.
Can you force devices to connect at 5G? NO. The device and Orbi advertise to each other what they are capable of and then the device decides which channel it will connect to. If the device gives adequate service at 2.4G, there is nothing to be gained by changing it to 5G.
