RLS works just fine on my Linux box, error detection and completion and formatting. Debugging is so so, not very good.
But on my Mac box, it's always crashing.
For me it's a) crashing quite often on Windows and Linux and b) doesn't really autocomplete anything beyond really simple cases where I don't need it like "Vec::<String>::" will give me new. But on most things it's just really awful.
Error detection, at least in VSCode is only displayed after compiling, that might be the plugin though.