Ruby's IDE

These days,I searched a good IDE for ruby because I like this language and start to learn.

I want the IDE can give me auto indent,syntax highlight,debug,quickly run test,refactor.

First one is FreeRIDE.It was taken by the one-click Windows Installer.It has some basic functions.But it is too simple can just edit code.have no project.

SCI,It is just an editor.But If you just want to write a small test,It may be convenient.

Eclipse + RDT,many people told me this was the best choice now.I tried it.Maybe it is better for guys who like using Eclipse to write Java Code.But I think it is too complex,especially I just want to run one file in a project.You should specify a file for the project to run.It is bad.

RadRails,it is good when you write project on rails.

Vim + FileTree + Ruby-Vim Configuration,I like this one.If you just want to write some script or just learn ruby,It is simple and have some good functions,except Refactor.(Can anyone tell me how to run the script in vim?)

Because I am new to ruby.Maybe you can tell me which one is better than the other?I want to have an IDE for ruby like Intellij IDEA for java.