Functionally spectacular as ever, Immy.
But... I don't think it's marketable. I understand and appreciate that it's a bare-bones, function-only model and that's what you built it to be, but because of that, I don't think it'd sell. The box art sells the model rather than any features it may posess and this is not the kind of thing I can imagine anyone purchasing by box art alone. I'm sure you could clad this in some way so it would be moderately eye-catching rather than looking like the inner workings of a machine.
I don't mean to be cruel and personally I think it performs its task far better than almost all of lego's own automated sets but that's not the kind of thing you can stress on a toyshop shelf.
It's not illegal, it's just cheating.
I'm into exam time right now... I'll be checking up frequently, but I don't expect to be posting in the next two weeks or so unless something really catches my eye.