I use Dreamweaver every day and it's very customizable. I've created a lot of menu items on the php tab that will insert many of the commonly used php functions and control structures with a click from a drop down list. With a click I insert all of my generic comment info and copyright notice that goes on every page. I've got all sorts of tools, manuals and pdf books available from a menu.
That being said, I've never looked at creating the autocomplete for the php functions but it might be able to be done. I'll have to look into it when I get the time.