Since you have a GPS, you can go with a cheap compass. I've travelled and hunted all over the nation with my GPS and my cheap Wal-mart compass. It has never let me down. In fact, if you are worried about durability buy 3 or 4 of them, they would still be better than a more expensive one that is not needed. Magnetic North is Magnetic North and degrees is degrees, don't spend much money on a compass. The $8 Wal-mart compass is all you need to accompany your GPS IMHO. Save your money and buy extra batteries for your pack!!