Phil:
>I have been looking at signing up with Vonage on their £9.99/month deal.

As far as I am concerned. the whole point of VoIP is to get free / cheap
calls, otherwise
you may as well pay OneTel £10.99 and get all geo calls 'free', without any
extra hardware and unreliability !
I have read reports of Vonage problems, similar to other VoIP providers.
Do note that the Vonage / Staple supplied ATA is locked to Vonage, but you
can buy it directly from broadbandbuyer.co.uk for ~£35 (Linksys PAP2).
Regards,
Martin