You have now seen a few examples of writing SIMD code on Arm with Rust.
Performance-wise, there is little difference between C and Rust as Rust is perfectly capable of generating the same assembly code as C in most cases. That said, if you want to program optimal SIMD code using the Arm ASIMD/Neon intrinsics, std::arch is the most obvious choice. If, however, your approach needs to be as portable as possible and you don’t want to spend time providing multiple implementations for each architecture then std::simd is a very viable alternative (even though it’s not part of the stable compiler yet).