One thing I've noticed with OnX is that the tracks don't always exactly follow the trails I've hiked. They can be as much as 10 yds off from what I can see using the satellite photos. Normally 10 yds is no big deal. If I can't find my way within 10 yds I'd better stay home. However, if I had to use an inaccurate waypoint to mark a dead elk in heavy cover it might be a different story.
Using my Garmin Montana with a HuntX chip for geocaching, I've found it accurate within 3'. I haven't yet used my phone and the Garmin side by side to check for the the phone's GPS accuracy.
