I have been on infinity for about 18 months, fairly reliable, at around 30-35 mb connection speed.
Only major problem is with BT sport, a problem I have lived with for the year or so I have had it.
Youview box is connected to gigabit switch served by Cat 5e cable (no powerline)
If i sit at my laptop, connected via viawi, and test speed on speedtest.net, I get around 30Mb/s
If i am watching a BT sport channel with athletics etc, no appreciable drop in speed.
If I am watching premier league football or recently the rugby final, the network speed drops to virtally nothing, and I get frequent IPC6023 errors
Are you using the BT HomeHub?
I don't know about your setup but maybe take a look at:
Can you try connecting youview box directly to HomeHub and not going through your switch?
I think I may have tried a direct line, (rather than through the switch) before.
Logically, it shouldn't make a difference, but I will try it next time there is a match on.
I am on a BT HH4.
I did have an asus router (asus rt-n66u) for a while, and I have convinced myself it was better, but it was unreliable, (kept dropping the broadband connection). I tried 2, and then gave up with that option