I've got one in the pack but only pull it out when I really need it (after trying for some time to discern my position via map alone). I'd use a bar mount more often (and get back to turning the pedals faster). Besides, it'll be another thing to distract my attention as I navigate a technical downhill, in other words: yet one more excuse for why I crashed. "I was doing just fine until I looked down to see whether I was going North or South, then this rock came out of nowhere..."