I assume you want consumer (home) broadband?
I heard good things about IDNET, but their FTTP 330/50 is £120(!) per month, over double the cost of their 160/30 (£51.60). Plus activation charge of what I believe to be £60.
Zen may be the best value for money. Have not used them myself, but heard they are one of the better mainstream ISPs. Under the impression their FTTP 330/50 is £76 per month, plus £55 activation.
There's also
Spectrum Internet which offers 330/50 for £49 per month for the first 6 months then £65.99 for the remaining 6 months of the contract, plus no activation fee. Unfortunately, not sure about their IPv6 support or whether IPv4 will be static - may be worth enquiring. Also been reading that their coverage is limited (apparently Wales and South West England), and I am not sure much of their reputation.
I would recommend A&A, but their prices can seem a bit eyewatering for most consumers considering quotas. It costs £100 to activate FTTP, plus the price for 2TB quota is £55 per month and is only 80/20. No 330/50 option available but they will sell you 160/30, which I imagine will be an extra £10 per month (like the cost difference between G.fast 160/30 and 160/50) - so £65/m for 160/30 with 2TB allowance, unless I am missing something.