Plz tell me I am wrong.

Happy to oblige :)I don't see why F# couldn't support refactorings like rename. I would even say refactoring is necessary in fewer instances (e.g. due to type inference, it's almost trivial in F# to wrap a primitive type in a more expressive type if needed - you don't need to go and change all the types, like you would have to do in C#. And afaik there is no refactoring for it either). Refactorings are never perfect anyway (e.g. if I rename a method in C#, and I call it via reflection, I need to go and update some string as well)Intellisense and its usefulness is very much in the eye of the beholder. I use intellisense fairly often with List, Seq and such, and have no problem with the module prefix.  I find it genuinly helpful. Don't know why you feel the there are too many matches with intellisense. I have the same "problem" when trying to find a class in a namespace in C#: too many options. Sometimes, it seems you really need to know for yourself what you're trying to do. Don't blame the hammer if you don't know where to hang the painting.