The Pro I am referring to is the AC Pro. The only Pro device you claim to have and yes not ER-4 since it is not a Pro. Now we have stating the obvious out of the way let's continue.
No the AC Pro DOES not beat the GT-AC5300 in performance! You have been drinking the kool-aid from your reddit buddies. Ever heard of this site we are on that actually tests these things?
Example: SmallNetBuilder (test revision 9 - 2x2 client):
UAP Pro: 5GHz UpDown Throughput: 433.7
RT-AC5300: 5GHz UpDown Throughput: 577.5
It is not possible to view the GT-AC5300 in revision 9. But after having BOTH the RT and GT the performance is very close though the GT is a bit better IMO.
Or check this comparison between the Pro and the HD + Synology RT2600ac:
https://www.custompcreview.com/revi...k-pro-touchbar-wi-fi-3x3-mimo-make-difference
There is a huge difference between old 3x3 AP's like the Pro and the newer 4x4 class as Tim also has elaborated here:
https://www.smallnetbuilder.com/wir...ll-a-new-ac-router-bring-you-wifi-joy?start=1
And you will be missing MU-MIMO - which is not really a miss - but also another dedicated 5GHz radio and that does improve performance when the network is congested. These are facts and not disputable. However on reddit there are a LOT of BS claims about the Pro's performance and I initially bought it to replace the RT-AC3200. I did not take long to discover that the AC Pro delivered 352 Mbps vs 760 Mbps the RT-AC3200 had on the same client. The Ubnt equipment went back. Today they at least have the HD AP's (normal and AP) so the performance of these devices are much better - that is why Maahfu bought them as he explained af few posts ago.