I've been on VM FTTP since April 2018, only other option is a rather slow VDSL line, or 4G although 5G might be available now.
Reliability and performance has generally been excellent.
I have had connection issues twice, and they were a complete mare to get fixed, had to resort to the forum on both occasions, telephone support were useless. Using modern mode completely throws then, they simply don't understand it. They are also obsessed with WiFi, and can't comprehend that a customer may know more than that do. So customer service/support is terrible on the phone.
Price rises are also relentless, I used to have give 30 days notice to get a decent deal, although on the odd occasion it was actually straight forward.
Now they've written the annual price rise into the contract there is no getting out of it and renegotiating, I think it's RPI plus 4% every April. So now will need to renegotiate at the end of the contract.
My IP address is very sticky, although it's different between modem mode and router mode.
If I had FTTP via OR available then I would not be with Virgin, but day to day performance of the connection is very good, and we don't get any slow downs, not even in peak times.
https://www.thinkbroadband.com/broadband/monitoring/quality/share/1d6fcf2a6171c36e1ae1f255513a45d3adad717a