Just remember that there are only two networks in this country. One is Virgin, the other is BT Openreach. So basically all the service providers apart from Virgin use the same two wires to your house. Just go for the best offer as the only difference will be the customer service side, which you won't know about until you have to contact them!
I have BT Fibre, never have a problem with PS4, Netflix, Firestick or watching Guiness on his porn webcam.
Are you sure about the two networks bit? I can't get Virgin because we don't have cable but I can get BT Infinity. That's two networks but where do Sky fit in? I've also been told that I can't get their high speed Internet so maybe they use Virgin's cable network?
Thing is, I'm pretty much stuck with BT and I've found their service to be crap and they are bloody expensive, though Virgin could be just as bad for all I know.