This pad has made a huge difference. I have a very sharp jawbone and the pain of my viola hickey was making me reluct to practice as much as I need to.
I can play now without thinking about my jaw - I can concentrate on the other important things an adult beginner needs to focus on. As an unexpected bonus, the thickness was perfect to put the instrument in just the right position to hold comfortably without stressing my shoulder or neck.
My only complaint is that after only 5 months, it doesn't reliable stick to my chin rest anymore, I find it stuck to odd places on my viola when I open my case and sometimes it falls off when I'm at a long rest and lower my viola.
Washing it didn't help and I don't want to use glue, so I am looking for a solution to that problem.