I'm in the UK and access the Internet through Virgin Media (formerly
Telewest Broadband). I'm on a 10Mbps service, but due to the limitaions of
my router (Linksys BEFSR41), I only get a max speed of around 6 Mbps. When I
disconnect the router and plug in directly to the cable modem, the speed
increases up to around 9.5 Mbps.

Vrigin Media are about to increase the speed to 20 Mbps very soon and later
in the year they will offer a 50Mbps service.

Therefore, I need a cable modem router that enables downstream speeds of up
to at least 50Mbps.

Does anyone know of any routers that would have this spec?

Thanks in advance