Large differences. Weight, feel, sound, price... It's really too large a question to answer... But the short one is that Poly and Carbon are not good options, and SS and Alu are pretty similar, though most prefer SS to Alu due to the weight.
Edit: Note, this is based on what I've read and what little experience I have with the subject. I've never tried Poly and Carbon, but Carbon is really expensive, and Poly flexes like... well, like Polyurethane.
Couldn't let this go without correcting it. Carbon fiber and polycarb plates (probably polycarbonate rather than polyurethane, though I think both have been made at one point or another) are not "bad" they just feel different. They have flex to them which many people like, for tactile Cherry switches especially. It's similar to having PCB mount switches.
Additionally, typically stainless steel has less flex than aluminum.
So its like stainless steel is an upgrade from alumunium and carbon is an upgrade to the polycarbonate plate yes?. I don't know what plate to use for my blue alps and green alps build. So its better to use the SS plate for green alps and linear cherry right? And carbon plate for tactile and clicky switches am I right?
That seems to be the most common preference, yes.
Thank you for the reply bro. What is your personal preferance if I may ask?
None are really better than any other. They just simply provide a different feel.
In order from most to least flex, I would rate it at, thin poly, thick poly, aluminum, SS. I don't have any experience with CF, but I would imagine it would fall between aluminum and stainless steel. The less flex, the harsher the bottom out feel is going to be. Though I reckon, a lot of people won't feel much difference, or if they can, it doesn't matter enough to warrant delegating a different plate material to different switches.
Though, one primary difference is going to be color. Acrylic and plolycarbonate are going to be a touch more difficult to paint due to being plastic and getting a proper primer to get good adhesion, but it is offered in a variety of colors. Plus, laser cutting plastics generally releases a lot of bad **** which needs to be cleaned out of the exhaust before it can be released to the atmosphere.
Now aluminum and titanium can both be anodized, which is an electrical applied chemical conversion coating that works in different ways for these two materials. For aluminum, when anodized, it actually produces hexagonal pores similar to honeycomb and then a dye is applied that soaks into these pores. This is the reason why color matching between batches is very difficult, because everything happens in a bath of chemicals and visual inspection during the process is impossible. Ti is a bit different in it changes the depth at which light absorbs into and reflects back. This difference in depth is what gives the different colors and can be adjusted by changing the amount of voltage. If the color desired is passed, you can't go back to a lower voltage and get it without mechanical removal of the anodized finish. However, one can go up to the next multiple of that voltage to get the color desired.
Now carbon steel and stainless steel have a bunch of different coatings possible not limited to traditional paint, powder coating, Cerakote, black oxide for carbon, black phosphate for stainless, etc.
