Deco E4 has 100Mbit ports, this is the best you'll get and it is consistent with what you are getting. Return E4 and get yourself M4 or M5, they have gigabit network ports and will support your router speed.

Also note that inside Deco app there is "Test Internet Speed" option which will run speedtest between Main Deco node and router/Internet. Run it and you should see it won't be getting more than 100Mbit, proving that bottleneck is Main Deco E4 network port.

@John_H Thats a bit of a downer, I need to think about and decide what to do next.  I must admitt it is a great improvement over my in-line Ethernet cable link up and beats the Netgear extender I have just returned.   

Thanks for getting back to me, its appreciated

John

@John_H 

Can you not return your E4 set? If you like Deco WiFi coverage and mesh, you can get Deco M4 or M5 set and it'll be same or better, plus no 100Mbit Ethernet bottleneck with Main Deco.

If you can't return them, there is another option: get single Deco M4 or M5 unit, make it Main Deco. Your E4 will be connected to it wirelessly as Satellite nodes, this will work and solve the 100Mbit port problem, as M4 and M5 have gigabit ports.

Of course, you might still find you are not getting what is expected, so strongly suggest getting M4 or M5 from where there is return policy. Otherwise, if that does not work to your expectations you'll end spending more money for not much.

@John_H I need to have a look at the store I bought it from and see what the say,  I am getting about twice what I had on my old configuration so it's not bad and it's stable so there is no pressure at the moment.