So the main cosmetic difference I see between anodizing and powder coating is that one remains shiny like the bare material is, while the other is matte. Strange though, as the standard Planck case is also anodized, but that one is matte.
If they are both equal when it comes to durability, wear, and such, I see no reason to just go with the one that is more readily available for you. And since you say you can't find a place that does high quality anodization, I would go for powder coating.
I try to scratch the powder coat with my nails and it hold still, scratch it with my bike key and it start to peel bit by bit, well, even anodize on a MacBook will scratched if you run another metal on top of it so yeah, durability is good. The red fire hydrant on the side road is a good example of powder coat on metal.
Seems like why peeps on mechkey prefer anodize is because it still "looks metal" because the material is what differentiate custom keyboard from mass-manufactured one and people want to show it off via pictures.
Good news is, my friend told me there is a workshop in the next city that do Hard Anodize (Type III). Already contacted them and will send them some plate with same material and dimension to see their quality.
Now that planck is in my options, I'd definitely want a hi-pro case. I hate the normal case.
I'd love a sample of the normal colours except for the the traffic blue. Light blue would be rad!
On second thought the traffic blue would go well with my Modern Selectric!
While I really want a new wave of color (pastel on this case) to be introduced to mechkey community, I find it lack the supporting keycaps with same saturation to pair it
that's why almost whatever keyset we all have up till now will only can be matched with standard color. The only key color to match pastel one is standard color like white, black and gray but I doubt gray will do it.
My other project is a keyset in pastel color scheme (the one I use in initial mockup render) in an effort to refresh the color game in mechkeys
(yes the color will be custom, not using SP's color chip).