RE: Scout Guard ?
The reason why the factory setting is set to 3MP is probably because the cam will still take a picture with good quality, but will save space on your memory card. The 5MP setting will definitely take a more detailed picture, however, the price you have to pay for a higher detailed picture is more memory consumption on your card. If you have a "bigger" memory card, then you can hold more pics. I would go with the 5MP setting and if you find that your memory card is filling up too quickly, then either drop the setting back to 3MP or get a bigger memory card. Make sure to check and see what the maximum size memory card your camera will support before buying a new card.