Also remember that a decent internet circuit delivers all of the theoretical bandwidth to the end users, whether that be one person downloading a file or many people performing multiple different transactions. A wireless access point will never deliver the theoretical bandwidth, the most I've ever seen is about 800Mbps for a single device and that was on an MR55 or MR56.
The bigger models are able to serve more clients at once with a lower latency and higher throughput. The MR57 and CW9166 can have two 5GHz radios alongside the 2.4GHz one, so can handle 30 voice clients at once or 90 data devices, whilst giving a good user experience.
We have found that MR44s are the best devices for low density areas such as corridors and fire exits, with CW9166s used in areas where more people spend more time. We don't use the 6GHz band yet...
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