I must admit that I have since I have easy access to one I don't think it sounds good at all to fret board is wrong for it on a Viola or other classical viol derivative its curved so you can hit strings without touching other ones, guitars as I'm sure you all know are flat so the most you could do is chords also I'm sure the rosin gunks up the strings which isn't as much ofaproblem in the case of a Viola because its almost exclusively bow, it would be interesting to see a guitar with a curved board for bowing, I can't however recommend a bow for guitar