MySQL Workbench is possibly the most unstable software I've ever used on a Mac.
IMHO the only two tools you'd want to use on a Mac for MySQL are
1. Navicat (ugly/annoying UI but great admin tools)
2. Querious (great UI but light on the admin tools)
Nonetheless, I'm a big fan of Coda for PHP development, even though there's no debugger. It's got a top-notch UI, great site configuration management tools, SFTP, FTPS/TLS, Subversion integration, solid syntax highlighting, and resource books built-in if you need them. Highly recommended!