@DBMandrake could you please describe how throughput can be measured? How about signal strength (you mentioned -65 dB as a good measure here)? I also have a TL-WN823N and wanted to compare its performance.
How do you know if you have a MIMO router? I have a D-Link DIR-850L. I found some sources that mention MIMO capabilities, but nothing on the D-Link site I referenced. Would I need to configure anything?