For as long as I have been developing web applications (well over 10 years) I have held to my favorite editors to get the job done. After all, a web editor is simply a glorified text editor, unless you develop with ASP.Net which requires you to pay exorbitant licensing fees just for the tools. Zend's PHP editor is the same way. That's why I'm trying Eclipse.
Microsoft is smart (there, I said it): If you want to program ASP.Net you need to buy both the server and the development tools from them. Don't forget about licensing Windows Server and MS-SQL. Smart. They screw both the programmers and the customers. But PHP is different.
PHP is free. So is the database, MySQL. So is Apache, the web server. And they all run on ALL operating systems - free and commercial - Linux, Mac OS X, Windows, etc.
While developing web applications I have used several tools: BBEdit, DreamWeaver, Nvu, TextEdit, Zend Studio, Notepad (when desperate), nano, vi, emacs and some others I'm sure I have forgotten.
By far, my favorite have been BBEdit and Zend Studio. BBEdit is great for manipulating text but that's about it. Zend, to me, is the king of the PHP development environments. It incorporates an editor, debugger, tester, documentation, Subversion, SQL database browser and tons of other great tools.
So, "why Eclipse" you may ask?
I love Zend. I use it daily. But I get the feeling that it is becoming the Microsoft Word of PHP Development. I don't use nearly as many of the functions in it as I should. Plus, it's expensive.
Zend is not software you purchase once and own it. You rent it. You have to buy it again every year. I'm not a big fan of that model. I don't mind renting services but if I'm paying a LOT of money for a piece of software, I want to be sure it's MINE.
Eclipse is free. It's an integrated development environment (IDE) that offers some amazing plugins.
So now I'm giving it a try. We'll see how well it does with subversion and my various projects. At first I was confused by it's startup screen. But it's running lean on my development computer (Powerbook 17" 1.5 GHz with a gig and a half of RAM).
The only problem I have seen is that a project I'm working on has several files in it and I think the Subversion download may have bombed out. I'll check in and update later...