I'm considering switching to Sky Talk to save 5 per month on the broadband. Sky also have a decent sounding offer on their line rental which would save me 40 over the next six months compared to BT. However, I'd like to be able to return to BT if need be and I've heard that in some cases there can be a hefty fee to move calls + line rental back (I think TalkTalk was mentioned as an offender).

Is this likely to happen with Sky? Is it the case since Sky Talk uses BT equipment anyway BT would take me back without cost? On a related note, does the Sky line rental have a minimum contract length? Sky say that their calls only package doesn't but the line rental is less clear.

Thanks for any information.