As long as you don't dabble in p2p, you'll be fine on talktalk LLU...you'll get line speeds 24/7, low pings, and stutter free video streaming. You'll be able to download at least 100GB per month on their Plus package before they raise an eyebrow. As for moving away from them, its possible to go directly from them to another full LLU service such as Sky or O2 though 9/10 times Sky, O2 etc will try to fob you off.
<now waits for others to say TalkTalk is the devil's spawn>
TalkTalk Plus LLU ADSL2+ connected @ 17612/1019 kbps
Attenuation 27db down / 9db up
Noise Margin 3.3 db down / 12db up
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