It has been very good so far. The visual studio support is excellent. You get code highlighting (of course), intellisense, you don't have to worry about building and compiling (just hit run), debugging, compilation is fast, execution is fast, there is an interactive repl. And last but not least: you get access to the whole suite of .NET libraries: http, gui libraries, parsers for various formats, access to databases, etc.

The most important annoyance is that you often need to explicitly upcast objects. For example if you have a String and a function that takes Object you need to upcast the String to Object.