Saw Mouse’s chat discussion about viola chinrests, so I thought I’d mention the Wave chinrests.
They come fitted for either violin or viola. I used to play with a center chinrest (Flesch center with “hump”). The Wave is somewhere in between a center & a side chinrest (and is mounted center over tailpiece). I play with a Wave I, 1 inch model now (been playing with it about 2 years now).
They’re a little pricey compared to other chinrests, but the owner lets you trial up to four models, & lets you send back w/money back any/all that don't work for you.
Here’s the link to the website—has good info/videos about head position, etc.,
Characterize people by their actions and you will never be fooled by their words.
Here's a little secret (not really secret): there is no difference between most violin and viola chinrests except for the length of the clamps. And with standard clamps, the only difference is the length of the barrels. You can easily convert any violin chinrest with standard clamps to a viola chinrest by swapping the clamps barrels with those from an existing viola chinrest, and vice versa.
For a while I tried using a Kreutzer chinrest (which I've only ever seen sold for violin) on my viola, simply borrowing the clamp barrels from the viola chinrest I used before.