There is no such thing as "modem only" outside of virginmedia. That is a firmware modification they made.
If you intend on using the ISP supplied router...
If you get Sky, do ask for the Sky Q Hub, it is usually a surcharge, but if you intend on using the ISP supplied device it is well worth paying for.
I think your gaming experience would be good with BT and Sky. I have used both and found both to be better than virginmedia for gaming. Damn, even my sky ADSL at 15Mbps was better than my virginmedia connection.
EDIT: To clarify, I am not saying using a modem is not possible, sure you can go out and buy one, but the ISPs do not supply a device capable of being a modem like virginmedia. E.g. BT will not have a "modem only" mode like virginmedia, nor will Sky, or will Talktalk. You would need to go out and purchase a modem such as a HG612 or a router with a build in vdsl2 modem.
Edited by ukhardy07 (Fri 16-Sep-16 19:03:53)