On your current connection it is slightly odd that you aren't getting either 8128 or 7616kbps DS trained rate.
If you switch to normal TalkTalk and they give you the free Turbo Boost option you should get well over double that. The drawbacks are you would be on an 18-month contract, and they take over your phone line as well, so it doesn't qualify as a BT line if you want to migrate out at the end of your contract. So you could be without broadband for several days then.
Instead, I recommend you look at:-
uno/xilo Pro 24 75GB, (you can't get the Pro 16 packages), and
vivaciti LLU 75, (you can't get the LLU Unlimited).
Note that the vivaciti price includes Vat, uno doesn't. So that would be £25.84.
On both your line stays with BT (Wholesale) though you can certainly get a phone package with vivaciti - I'm not sure about uno. The broadband is a monthly contract.
Bob's broadband basic info/help site:
www.robertos.me.uk
ISP history: Demon dialup >> Freeserve dialup >> BT Broadband >> Prodigynet >> Newnet >> O2 Standard.
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