I might go for VM M200 for £30 a month and ditch FTTC. https://www.virginmedia.com/shop/broadband/compare?navelement=black_friday_2019_bbcompare
You may argue that those are only my own experience. When you say vm are much better, did you mean within the last 12 months they've improved a lot?Apparently even the last year's ofcom report (Nov 2018 Source: https://www.ofcom.org.uk/__data/assets/pdf_file/0020/147332/home-broadband-report-2018.pdf) shows that vm are one of if not the worst major ISP in terms of web loading speed, latency, upstream jitter(due to the much lower upload speeds) , packet loss, DNS resolution time and most of their packages are not as good as their competitors at online streaming.