We were on a fixed wireless service here for a few years (not spot) but we recently got FTTP and we went with Zen due to work of mouth reviews aswell as on here, very pleased.
We went with the 100M option in october and its been rock solid since. We also upgraded to a Deco Mesh wireless router and havent had any issues, we have the zen supplied router as a backup incase but they are totally fine with you using your own hardware (aslong as it can cope with the speeds).
As others have said there are probably faster/cheaper providers but for the quality of the customer service etc... I highly recommend Zen.
Zen Full Fibre 100