Hi Noah,
I’ve seen people use them. I’ve only seen them at old-time jams used by older beginners.
I don’t know one from the other. It seems that the people that use them are dealing with some type of orthopedic issue that prevents a “classic hold” on the instrument.
I’ve never used one and would not encourage or discourage there use. I don’t know enough.
There is a YouTube of Darrol Anger reviewing the Aceto, he likes it.
Maybe someone will chime that has better knowledge.
George
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