I'll continue to carry/use both.
I used an older Garmin for years and like the accuracy of the way points, recently upgraded to a newer model. I agree the user interface can be archaic. However in the dark or white-outs it makes a big difference. I hunt some areas where a GPS helps alot at night, faint or no trail - make a wrong turn and you find yourself lost in the dark, no moon, deep in the nasty stuff. Led headlamp and flashlight both on full burn. Not fun at all.
I can recall a few times I left my handheld GPS to save weight and wound up regretting it. And I can recall many times a GPS saved me alot of grief.
Onyx maps is great for property or boundary lines but I usually leave my phone off most of the time if away from the truck more than a day since it eats the charge. Could try one of those solar chargers, more costs and weight to pack though. I just turn my phone on periodically if needed to make a phone call, some places no signal.
Use offline Onx maps and put the phone on airplane. The battery will last MUCH longer.
Next weekend I'll be laying out a snowshoe orienteering course for a some Trail Life troops. I have the points set in my Garmin as it will locate them within 3'. Onx on my phone isn't accurate enough for this job. I honestly don't think doing this in snow will accomplish much. The boys will just follow my tracks.
