I paid for pro last year just because I was looking at it so much. I like to pay for good things so that they stay there. Can't remember how much it was.
Cycle.travel for me. My digital OS maps are getting a bit old now, which led to me being caught out a couple of times by new housing developments and road changes. Paying for cycle.travel adds up-to-date OS maps to the list of map types that it offers. That saves me paying for an OS subscription directly.There are a few things, RideWithGPS is another one, that I don't mind paying a few quid for because I want to make sure they stick around.