I've just renewed the Gold membership for the 2nd year. It works for me as I'm not a horse owner. I got it first when a kind local lass let me take her Fell out hacking. It gave her peace of mind to know that I had cover if something happened to me. Oddly enough I didn't get it for my personal cover - it was more to offer the loaner reassurance that there was cover for third party incidents and her animal is something should happen. (In the village centre a horse once went up and came down on a car bonnet - no harm done to rider or horse, but it took a hell of a lot of sorting out.)
I've not had to make a claim, and there may well be better ways of handling it if you have your own horse/pony. I just feel I should take some responsibility if I ride someone else's horse, particularly if there is no contract and no money changes hands.