I've programmed for six years, and in that time, I've never used a PHP IDE. I feel perfectly fine using Vim, the Linux shell, MySQL command line and Subversion command line for my web application development. When I'm asked to work on other people's projects, or open source projects, I can generally find my way around after a quick system architecture overview.
Recently, I was curious about PHP IDEs. I downloaded NetBeans, but I lost patience debugging installation problems.
It makes me wonder, will my productivity increase substantially with the use of a good PHP IDE? What percentage of LAMP/PHP developers use a PHP IDE?
I always use an IDE now, if it supports refactoring. I may use it in addition to, or alongside, Vim or Emacs, but refactoring is now an integral part of my development style and having automated refactoring tools is essential.
If you're only going to use the editor features of whatever IDE you choose, you probably won't benefit much. The benefit is when: