This product is very effective and useful, when you can use it. If you have a Garmin gps, I recommend it 100%. However, if you planned to use it on your smartphone or pc, i would look somewhere else. To use on a pc, you have to download a program called Basecamp from the Hunting GPS Maps website. Then you have to plug in the sd card and download the files. Its overly complicated. They should give you a CD for pcs and the sd card for gps. Also, they should make it compatible with android phones. It would make it so much more accessible for people without a garmin gps.
In closing, if you have a garmin gps, i would recommend this product. Otherwise, stay away.