My son just purchased a Conn Director 27M with the serial number 16408AJ072. I asked before buying it if it was a Mexican model or had the "N" first in the serial and was told it is neither. Can anyone tell me more specific info about this model and what it should cost in "excelent condition"? I would also be interested in what the differences are between this and the, so to speak, student models are. Thanks for the help!!