I just ride lesson horses now.
They LIKE the Haas brushes. The Schimmel seems popular even with the sensitive skinned horses though it feels harsh on my hand. They also LIKE the New Generation curry comb especially the super sensitive skinned ones which cringe from every other curry comb. Haas brushes for the win, your horse will tell you his/her favorite Haas brush. I like these brushes myself because I end up using a lot less effort to get the horses CLEAN and shiny. My riding teacher also likes my Haas brushes.
These horses also like the Postures Prep cross fiber groomer (really a fascia tool not a grooming tool). I have gotten nuzzles from a particularly closed down super reliable slow lesson horse. He travels better if I get to use it LIGHTLY down both sides of his spine and on his hind end muscles that combine to form the hamstring.
The lesson horses with thicker, less sensitive and often much itchier skin have LOVED my HandsOn grooming gloves, however the sensitive skinned horses just cringe when I try them on their skin. The less sensitive horses love that I FINALLY get all those pesky itches that drive them crazy and no other grooming tool works for them.
The Tiger’s Tongue grooming tool (looks like a coarse sponge) is also well accepted by sensitive horses. I have not used this one as much since I got all my Haas brushes.