The important thing is that any navigation device can and will malfunction under a specific set of conditions. That said, a decent compass is generally more foolproof than a GPS receiver and does not rely on batteries.

It doesn't mean a compass will work well all the time. I've had a Suunto MC-2G develop a bubble at the worst possible moment, throwing off accuracy (by a totally unpredicatable margin) when I really needed it. But I've also had a quality GPS receiver freeze more than once, not to mention the times I couldn't get a good signal in difficult terrain, making the device pretty much useless for accurate land navigation.

Bottom line, whatever navigation device you use always double-check everything in the field - keep looking at the map if terrain features match, check the direction of sun/shadows... The more you know, the less you need to carry. All basic common sense stuff.