cablevision blows. even with recent changes the interface is still 10 years behind FIOS. Be happy if you can jump off cable into FIOS.
However FIOS is more expensive & verizon customer service sucks where cablevision has better customer service if you have problems.
PS - you can use the verizon FIOS documents to call cablevision & ask for a lower price. they will give you their lowest price in order to keep you. when you call to disconnect you will be xfered to the retention dept, tell them you signed with FIOS & they will offer you cheap deal if you stay.
