David,

I've been using silver and gold aluminum as the canvas for award plates.

I don't think it's possible (or at least easy) to get smooth transitions of gradients with laser sublimation, because laser printers rely on redepositing of toner to the rollers, as opposed to the ink jet's single pass operation.

Ink jet sublimation isn't as scary as it once was, mainly because the ink is much more stable than in its early days.

David "The Stunt Engraver" Lavaneri
DGL Engraving
Port Hueneme, CA