Went ahead and contacted M2C last night regarding a possible future chassis for the XTR out of curiosity, they responded this morning.

They replied in an email saying basically that they are closely watching the progress of the popularity of the XTR.

I would assume this means if the truck becomes popular enough, they will make a chassis for it. Other parts - probably not unless it becomes EXTREMELY popular like the Arrmas. However I would say at the rate things are going, there is a fairly good chance of eventually getting a 4mm Chassis for it from M2C, so long as the popularity growth continues.