Also see syntax-checking running-tools-or-compilers eclim
debugging: vdebug, vim-addon-xdebug
completion: based on tag files, so make sure you use ctags
manual in text form: https://github.com/MarcWeber/vim-addon-php-manual This might be outdated, you can update it and sent pull requests
syntax highlighting is known to be slow. By tweaking synmaxcol etc you can take some control.
TIP: its trivial to catch exceptions, write them to a file and load that into quickfix. github.com/MarcWeber/php-essentials has one implemenation - you may want to write your own.