Pros:- Alloys are normally lighter than the normal disc so There supposed to be FE friendly. They add that cathchy look to your ride as well if you select the right ones. They don't wear easily as normal disk. No rust as its alloy material.
Cons: if There is a bend u can't fix it unless you have a hydraulic press available in your city.normally they don't bend but guess what, we are in the pot hole capital of the world