I have the Trifecta sheepskin halfpad for my old man and, since we are in between saddles right now, it is a necessary part of his wardrobe. With it my saddle and the one his kid (who is leasing him) has fit him great.
When I find a saddle narrow enough to fit him I’ll switch to what I use on my other horse, which is the Contender II (it combines Back on Track with an Ultra Thinline). I have a couple of those in black for daily use and then a couple of white ones with his show name on for showing. Or, I’ll use my regular Thinline pad over a square pad.
I love Thinline stuff- it doesn’t interfere with saddle fit, the half pad and the squares have the Thinline divided on either side so there is nothing to bind under the pommel, and I think they help both my back and my horses’s backs.