I own both a Greg Mouton Accordion (Bb pictured in the header and below) and a Shine Mouton D accordion.
Both accordions are excellent. As far as the Bb that Greg made for me, I've never seen anyone who takes the time to POLISH the wire lifters and screws!
Greg Mouton is a wonderful, honest person and a terrific craftsman. I would venture to say that Greg's ONLY fault is that he make take awhile to make an accordion for you if you order one. He runs a music store and ALWAYS stops whatever he's doing to have a discussion or offer advice. He's a very friendly guy. When I ordered this accordion from him, he was doing all the work himself. He may have his son helping him at this point.
I dropped in one time with a brand new Martin C accordion that had gone badly out of tune. Greg retuned it for me at no charge.