Hello Jim
the M-3PX is more or less a M645 – I had one around 2012 and sold to a customer in 2106 I think. I will check my office tomorrow for the detail.
I have been representing Sound Lab in Japan since 2012 and am recently giving support to anyone anywhere – please let me know if you have any specific questions I might try to answer.
I have a website with some information which may be interesting … but it is still in progress and will update more soon with information.