I have set up an incoming number with VoipCheap.co.uk. This connects ok.
However when other people dial this number they do not hear the standard
British ringing tone. I'm using a Linksys spa3102 but it is the same for
the software client.

Is there anyway to fix this. Presumably it is the same for all Betamax
products like VoipCheap.com (which appears to have free uk calls while
the .co.uk version doesn't)

If not are their any recommendations for a voip provider for an incoming
line. I would like to port my BT number and so I'm concerned about
reliability (and maybe the need to port out in future). I would be happy
to pay for a deal with bundled calls like Vonage. Is Vonage reliable?

I would also be ok with using one provider for incoming calls and
another for outgoing.