Not necessarily. Take a look at FreeView - unless there are channels that you really want that are available only on NTL then FreeView is an excellent alternative. With the demise of Sky One on NTL our NTL (guess I should say 'VirginMedia') box is now not in use - we use FreeView instead with a hard-disk recorder.
For other rooms in your house a FreeView decoder can cost as little as £30 and you have nothing else to pay. Many recent TVs now also include a digital FreeView decoder in the box - so you may already have something suiteable.
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