I'd say it is pretty bad[1], but the F# REPL is decent at least.

1. https://github.com/dotnet/roslyn/issues/26934

Echoing the other comment, personally I find the C# interactive really frustrating to use. So close and yet so far.

I often find it quicker/less frustrating to just fire up a new console app project.

Last time I tried to use it I think it was even running an old version of .Net and you have to remember to switch the version.

Yes I saw the REPL in VS 2022 and Jetbrains Rider, but I still prefer having this utility at hand with a collection of scripts ready whenever I need to script up something, or experiment with a service or database, or learn something new in .NET.

Not even in the same zip code.