I had problems with this printer on cotton and semi cotton canvases - no matter how I tried I couldn't get reasonable Dmax. The ink in dark areas was "washing itself" from the top of cotton weaves. I did tests with canvases from many suppliers, but no love. Maybe my client didn't try really good canvases, optimised for this kind of inkset.
The results on poly canvas were excellent, I've never seen such stunning quality on any other solvent printer, and it's pretty close to water-based inkjet quality. But my overall impression is that Epson's super-eco-eco-eco-solvent ink is much more demanding than typical eco-solvent ink, and in case of many ecosolvent media like canvases and wallpapers can be a real PITA and calibration nightmare. My advise is to give it a good test drive before you buy it.
As any other solvent printer it's durable - the pigment is melted into the surface, so after it gets dry it's virtually like laminate. In case of water-based inkjet the pigment creates a layer on top of paper/canvas coating, so it's much less scratch resistant.