@Kazze 

Deco M5 should be able to do better. 

I have M5 with same hardware and firmware versions. It runs in AP mode.

For speed test, I am using Ookla speedtest app on Windows desktop, installed from Microsoft store.

My ISP router: Hitron CODA-4592.

My ISP connection is gigabit.

My network layout: over 10ft long Cat 5e cable from ISP router to gigabit switch TEG-S80g, another 10ft long Cat 5e cable from switch to Deco M5.

For tests, I have desktop connected either directly to switch by 1ft cable, or to Deco M5 by yet another 10ft Cat 5e cable.

Running speedtest on desktop connected to switch results in 940Mbps.

Running speedtest on desktop connected to M5 results in 850-920Mbps.

Things I noticed:

1) Deco M5 performed better with firmware 1.5.0: I could get consistent 920Mbps results on every speed test. With current 1.5.3 firmware speedtest results vary between 800-920Mbps.

2) It takes longer for Ookla speedtest app to reach max download speed when desktop connected through M5, that hasn't changed between firmware versions. Often it is up to 14-15 seconds to get to peak, just about when speedtest app ends its test. When desktop is connected directly to switch, Ookla app reaches max speed at under 7 seconds and stays at peak for the rest of the test.

Thanks for your input!

I have a hard time to blame it on the hardware as well... tried the other "pucks" as well.. no difference there. It's a pity, I am actually considering to return them even though I kind of like them (overall for this price), the wifi speed can be debatable but the wired speed is a "no-brainer" if you ask me..

br

Kazze