Lacrosse pocket placement?

what is the best place to put a pocket on a defensive lacrosse head (the middle of the head, mid-upper, lower? im a defensive player and im getting an STX Xcalibur head custom strung with a canadian, traditional hard pocket, uruthane coated hard pocket, or 10 diamond high tenacity hard pocket) ALSO what is the best kind of those pockets i just went over?