You can have readonly properties and automatically generated initializers.

C structs are a pain to deal with when you’re working in Objective-C. No way to add custom (immutable) methods nicely . It doesn’t play well with Foundation primitives such as collections. No runtime interoperability.

This is a very nice concept to have, but C structs are ill-fitting. C++ classes seem to be a better fit, not sure how it plays with ARC though.