I'm not sure about big box store lights but when I set up motion activated lighting control I look at the following.
The distance and the area I'm trying to target, then check the specs of the motion and see if they comply. Any good motion should give you the angel of the spread so you can calculate your coverage. Better motions are not only passive IR sensors (looking for heat and motion) but have microwave detection.
These guys make good outdoor motions (not sure if you can tie em into your lights easily though):
http://www.optexamerica.com/
The distance and the area I'm trying to target, then check the specs of the motion and see if they comply. Any good motion should give you the angel of the spread so you can calculate your coverage. Better motions are not only passive IR sensors (looking for heat and motion) but have microwave detection.
These guys make good outdoor motions (not sure if you can tie em into your lights easily though):
http://www.optexamerica.com/