I've tried the last two major versions of PHPStorm and I just can't use it. On my Air with 4GB of RAM it struggles to even open a file. It's slow, sometimes unresponsive, and uses so much memory so my VM can't run on the same machine. If there was a 'Lite' version, I'd love to try it out. But the defacto PHP IDE can not run on my machine, which is why I stick with ST and plugins.