ISP Reviews by rayrob

Symmetric 1Gb/s via CityFibre - £20 pcm (+£2 each April)

Nearly 3 months in and I'm a happy customer so far.

Some administrative bumps with the install but the physical work by CityFibre was fine.
Once in and running I was impressed with the speed.

Supplied router (Linksys SPNM60) was fine (firmware a little basic). Good hardware specs and both ONT (10Gb) & router ready for 2.5Gb/s so easy to upgrade package in the future.
Annoyingly, when enabling/disabling the guest network the router re-assigns the first IPv6 range from the prefix to it causing the main network to renumber.
I replaced it with an OpenWrt router and hope that soon OpenWrt will be available for the SPNM60.

Service has been very reliable for me with only only 1 interruption that affected many other users. Seemed to only affect IPv4 (so perhaps CGNAT related?). Reddit users have reported more problems, even in my town, but it's been good for me so far.
IPv6 prefix has remain the same as has the CGNAT IPv4 address.

I moved from Sky Fibre to the same package (Openreach 150/30) on Vodafone. No engineer needed as existing fibre. Switch went fine and was actually early - about 18:00 the day before planned date.
There was a noticeable improvement in web page loading. Sky was fine Vodafone but feels a bit snappier. Couldn't say if it down to network or hub etc. Bandwidth test score marginally better.
The new 'Power Hub' is a decent spec.
IPv6 is present with a /56 delegation and works well (same as with Sky).
Decent deal when you take into account a £90 giftcard via MoneySavingExpert. This arrived earlier than expected after about two months.
I have had no need to contact support so far so I can't comment on that.

Update after 2 years and moving on (to toob/CityFibre):
I was generally happy with Vodafone, the only issues were:
No static IPv6 prefix available (even if you have static IPv4)
Both IPv4 and IPv6 change every time the router reconnects
The new addresses assigned could appear to be anywhere in the country so for a while some site's GeoIP was way out (showing nearest store many counties away)
The tobi automated support assistant is next to useless.