I am no fan of the BT Hubs but in response to your post I would say:-
First of all you can get a VDSL Modem/router for about £30 and it costs £35 to lodge a claim at the Small Claims court so your comment about taking BT to the small claims court being cheaper is not correct. You might not win and have to pay costs to BT.
Second: Have you established that it is the hub that is faulty and not your actual connection, your equipment or internal wiring or some other source such as interference. Until you have done that you are only guessing it is a hub problem.
the probablility od continually getting a faulty hub is remote so I agree with @gg30340 should be more looking into your connection and checking your line as that is more likely to cause problem.
I have used many hubs at varying times and never had the problems you descibe there are many people who do have hub problems and who post on the forum but based on number of hubs in use and my own experience they are the minority
if you want help from forum then post stats from your hub
check quiet line test
are you using the test socket with a filter to eliminate internal wiring and faceplate from causing problems