I'm currently using John Lewis standard fibre (i.e. "provided by Plusnet"), where I get 40mbit sync. I'm looking at switching to Plusnet Fibre Extra, and the estimated speed shown when putting in my details is 36mbit to 52mbit. Is there any other way of getting an idea of what it might be, without signing up to a lengthy contract?
When I was on ADSL, my actual speeds were significantly higher than the estimate, but I don't know if it works a lot differently on fibre, or if any of my line sync statistics might give an indication.