I wonder what stuff are you using when coding in PHP (talking about IDE now)?
I, personally, just love phpED IDE, fast, ultra convenient, advanced and clean debugger (comparing with Zend Studio debugger, when it comes to add again and again dummy.php file) .
Several weeks ago tried to use Zend Studio, didn't make the impression like phpED, although, it has several unique features like "Code analyzer" and very enchanted code insight (better that phpED's).
These two are the biggest competitors in PHP IDE market for me.
Maybe eclipse, but... Something is wrong for me in this product (no offence guys) .
Zend Studio if I’m working on a complex project, otherwise I’ll usually use pico or vim. I like the syntax highlighting, variable completion, and function parameter helpers in Zend, however it is not coded very well and is rather slow and bulky.
I always use Kate or KWrite I love the different plugins and wide range of syntax highlighting, I used to use phpedit (I think was its name) years ago but I find text editors a lot faster now