I recently upgraded to Ultrafast and as part of this upgrade I got sent a new Smarthub 2.
Testing the speed from my phone and computer I found that the speed seem to have dropped - from 50 to about 32, and certainly not the 150 as expected.
I was connected to the Fibre helpline ( in Exeter ) and I was directed through all the usual steps - re setting modem and hub etc but with no improvement.
They could see all details of my set up, including the fact that 150mbs was being delivered to my house.
As a last resort he suggested replacing the Smarthub 2 with the original Smarthub....and bingo, full speed resumed.
He suggested that this could be because the 5ghz band is locked down in the SH2 so it can operate with the mesh network that can be set up. So if you are having less than expected speeds with your new hub, try going back to the old one.
During all the testing I also found that the Speedtest.net app was always giving a lower and more erratic result than others - fast.com and Google Speed. Not sure why.
The world's your oyster as it would suit your specific needs and budget.
What I find right for my needs may not fit yours