Any thoughts on dedicated off road gps units like Garmin Tread or Magellan TRX or others?

[2015 Z Force 800 53/Trail EPS]

I'm using tablets now with either 600 or 1000 nit displays with Backcountry navigator Pro and/or OruxMaps. I do put them in good cases for protection. I do have a Magellan TRX-7 barely used I paid over 500 bucks for that I would be willing to let go for ..say 300. Great unit. I use it in my truck sometimes. I just needed something brighter for my old eyes out on the desert trails. 

Not dedicated but i use OnX Off road and download the HD offline maps before i leave the house for the area im playing in. Have a phone mount next to the speedo so i can see where im at with a glance. Keep it charged with the USB on the quad. Bigger display would be nice for sure but i guess im cheap.

I prefer Gaia GPS.  They seem to have the best maps and their system for setting up your own track works great. 
System works on Widows 10 android and iPhone and iPad.  I use the system on my Windows computer to make a track, save it and it available on my phone.  All you  have to do is to insure you download the map you want to use on your phone prior to heading out since you need a connection to download maps. Cost of the premimum progam is $2.33 a month which allows access to 300+ maps (which can be layered) and offline use. There is a free version but doesn't work offline.

I've always used a garmin 650 Montana
Easy to use touch screen
I used to make maps on google earth an import to the gps worked amazing

But now a days a tablet with built in gps is the way to go even a Samsung a tab is less then half the cost an it's a tablet so there's much more you can do on it

Though not consistently, I use OnX Off road and download the HD offline maps for the region I'm playing in before I leave the house. Put a phone mount nearby the speedometer so I can quickly see my whereabouts. Use the quad's USB port to keep it charged. Larger display would be good, but I guess I'm cheap.