Is it right that the TD-W8970 cannot be used with BT Infinity at all (unless I use it as a raw router without an ADSL connection)? I bouthg one the other day being assured it will adequately replace my Home Hub 5 but I cannot get it to connect.
The TD-W8970 contains a ADSL2+ modem. To replace a home hub 5 entirely you need a router that contains a VDSL modem. There are some available but not many if your looking for wireless AC which the home hub has.
You can use the hub as a modem (kinda) and connect the router to it so the home hub is only managing the broadband connection and the router is managing your internal network or you could buy an open reach modem for around £15 on ebay to go with your router