I don't know anything about them but here is a link to their web site http://www.mandmgoldexchange.com/
Personally I would NEVER sell my gold (or silver) to a "buyer" that I have to "send" it to - when you set it on the counter & deal "face to face" you have the option to except the offered buy price & walk out with the cash - or - pick up the gold & walk out with it
"sending" gold to a refiner with a good reputation is another story