I worry about the sales of the metal tanks not meeting their expectations, and they give up on the idea. However if sales are slow( I have no actual idea if this is the case) part of this could be because we all have plastic version of these tanks already. If Mato produced a metal version of a tank that wasn't yet produced at this price point, I think they would have a runaway hit.
Cheers
I agree Dan,
I see why they would want to test this with a proven design, but I don't see this one taking off for the simple reason you mention, a lot of modelers have the StuG already. Personally, I don't see the need for all metal past the lower, but I like to alter these thing extensively, so metal works against that. But at the $600 price point, with the need to drop another $200-300 into it to run, you're in Tamiya's territory, so unless you come out with something they don't offer (like the StuG), you're fighting a tough battle.