Sky - Fibre Optic.
It's alright. Only ISP who've offered us FibreOp at a reasonable price.
And the speeds should be pretty decent, but are usually not matching what they say it should.
In particular is our Wifi. The router they provided for us is terrible (as are previous routers we've had), and there's a number of deadspots throughout the house.
Best thing about Sky though is that we get a bit of a deal in their combined TV, Internet and Phone package.