the stock props are desined for the plane, your best option is still try somthing diferent if your not liking the ones your using, generally the less the pitch the slower you fly.
lower pitch props have more torque, higher pitch more speed can be atained, of course dia. plays into it, smaller dia.higher RPM's.
I would try the stock one and see what you think.
did you not get a stock prop with the plane?