The code conventions say that using && and || is "wrong":
&&
||
Is there any advantage to using AND and OR besides clarity?
AND
OR
The truth tables for the operators are the same, the only difference is the priority:
http://php.net/manual/en/language.operators.logical.php
http://www.php.net/manual/en/language.operators.precedence.php
Just make sure that any agreement you decide to accept is consistent throughout. Otherwise, priority issues haunt your code.