Wish I had a choice but that's life, at least BT where I am is excellent otherwise I would be pulling my hair out.
If you mean BT Broadband then there's only a very few exchanges in remote parts of Scotland and the like where that is true.
In nearly every exchange in the country you can choose nearly every ISP in the country.
True, they use BT Wholesale, just like BT Broadband do. But the performance and price differences are huge. Usually in favour of the non-BT Broadband, though I have to admit for some people it is fine.
My broadband basic info/help site - www.robertos.me.uk
My domains,website and mail hosting - Tsohost.
Internet connection - O2 Standard.