Chin rest fitting
I live in a town that does not have a string shop or luthier. I am unhappy with my current viola chin rest and as it happens, I am headed to a city next week that has several fine shops. Do you think it's necessary to take my viola with me (which would be a pain, as I am flying) or would using a stand-in/shop instrument suffice when determining which chin rest is best for me? Bottom line: I'll take it if I must, but would rather not.
I'd say with violas especially the size and dimentions of your viola could certainly affect your chinrest choice particularly its position (side or center), but if this were a violin, I'd say there's less impact because violins are more uniform in size. I think that if you really had to, you could try chinrests on a viola that's the same size as your own and hopefully with similar dimentions. At least you can probably get a clearer picture of what shape of chinrest would be best for you.
I suggest measuring your viola length, width of the upper and lower bouts and thickness at the chinrest position and if you can try your chinrest test samples on a similar size viola.