Mantic are also experimenting with a new material for their miniatures which they are calling 'resin plastic', apparently it holds detail just as well as metal but is around half the cost. Mantic have posted this video:
unfortunately there are no close-up pictures yet but hopefully soon. I'll definitely be picking up more of Mantic's stuff if the 'metal' models will be half the price they were before.
Looks like Mantic are doing the smart thing and using ingenuity to help them meet the demands of their customers rather than just saying 'it can't be done'.