I use Visual studio or Notepad++

I've gone through a few...

• Notepad++ (Enjoyed it, but some of the rough edges got to me; as did not being able to use it cross-platform.)
• Aptana (A full-on IDE, the plugin that added support for ASP/VBScript left a little to be desired. Plus it was a little too much for quick edits.)
• WebMatrix (Another full-on IDE, supported syntax highlighting for ASP/VBScript, Git, and a lot of other fun extras. Was a bit too slow to start, and was a bit too much for quick work)
• Sublime Text (light-weight text editor, really nice but I had to fight to work around the restrictions at work to install the modules I needed...)
• Visual Studio Code (light-weight text editor, still in beta - v0.5.0 as I write this. Love it, works well at work and on my Mac/Linux machines. My current go-to for quick work.)

I've got a copy of Visual Studio 2015 Community downloaded, and I plan on installing and giving it a spin this weekend.
The best one is the one you actually use and enjoy.

Odd place for this topic, but ok. I've used a number of them, but did my last few thousand pieces on UEStudio.

I use vim and gvim mostly.