I think my first 20' length cost $80 ($4/ft). Now it's twice that! But what isn't 22 years later? I 'think' I'm up to 60' (3 sets) and desperately in need of going to 80' (4th rubrail).
It always wears out on the bow first(you can see the fraying in this photo 2 years old). Both from running into docks and boats and from abrasion from above(we have a dinghy tie off that rubs on it). I may just replace a bow section this time, to get a few more years out of it. I tack it on with little bronze ringed boat nails.
But it works great. You can't scratch a boat and I've never heard my dinghy bumping the boat at night.