I switched to Sky Broadband and all I had was trouble with the WiFi dropping continuously throughout the day.
Was onto Sky for over 6 months asking them to sort it out, but they said that there was no problem.
Now, I had no problems whatsoever before I switched.
Fortunately, they wanted to increase the cost mid-contract, which gave me a reason to leave them penalty free.
I switched to another ISP immediately and have had zero problems since.
I would not recommend Sky broadband to anyone.