I am going to say something good about BT "People" but not their wires.
Last time I came on these forums my heart sank. I was having all the broadband problems discussed here and I was apprehensive about getting a solution. Having moved from central London to a rural location in the Scottish Borders I went from high speed fibre to ADSL over a 5km copper wire. Having had good service from O2 on my mobile I signed up for their broadband. Big mistake. They fell foul of the infrastructure problems and were either totally unable or totally unwilling to even try to sort them. I ditched them and went directly with BT so I could force them to address the hardware issues. After all it was their wires and their exchange (not unbundled).
I had to start with the call centres in India. It was slow and pedantic low level stuff to start with but I guess that is probably appropriate for the bulk of customer issues. The young people I dealt with were courteous and as helpful as possible given their requirement to stick to the corporate script. I decided to respond in a similar patient but determined manner and they responded in a positive manner. Eventually my case was escalated to a priority level. There is a system! They sent in several engineers with differing skill sets. They were each competent in their own area but progress was slow because of the need to re-profile and settle down after each change. One engineer went well beyond the routine and even seemed to have a personal commitment to solve my issues over and above his corporate responsibilities.
I have agreed after about two months to close my case. My speed has settled at 2.5MB (from dipping as low as 0.125MB through repeated re-profiling by BT software at the exchange.) There is an identified cable fault outside my village which will be repaired and hopefully further improve my speed. I probably will not ever see "Infinity" in my village.
Be patient. Their wires are AWFUL but they are very old. The people themselves are excellent but they have to work withing their corporate systems and on the awful wires. They WILL get you there in the end.