When my fttp was first installed (i order the 900 package), there was a problem with the profile so I only got the speeds of the fibre 150 package which was 150 down and 50 up. This took about a month to resolve. In the meantime, it was however a noticable improvement over the 77/18 I previously had using ADSL.
For day to day use (browsing forums, facebook, remote desktop, zoom meetings etc.) there's not much difference from the 150/50 package. Forums threads open slightly "snappier", webmail opens almost instantly etc.
Where I notice a difference is viewing content with a lot of photos (e.g. several photography forums), large downloads. When uploading batches of hi-res photos via ftp, wetransfer etc. the time saving can be a few minutes. I also have a few heavy internet users in my house with both sons heavily into gaming/streaming. Since getting the full 900, I no longer notice any difference in performance regardless of what they are watching/downloading as they can no longer saturate the link. This alone is worth the £30/month extra over the 150 package.