My preference would be to stick with Garmin but then I've always liked a proper map.
I can appreciate the use of a map on screen but in my opinion of those I've seen still prefer a map. Trouble with a screen is you have to scroll left/right up/down to view over an area, its like looking with blinkers to me. Bigger screen yes, that would help, like an Ipad or similar, but then it reaches a point where you may as well have a folded map.
I've never gone for a map GPS either, for the same reasons as above, screen size is too small to be of any use, hence my choice of the Etrex 10, purely for Waypoints and location as and when needed.
I know a few who swear by Viewranger or Satmap. but not for me. Waterproof, doubtful although there are ways to keep damp to a minimum with use of drybags etc.
Satmap I didn't like the buttons etc, something about it seemed cheap, which it isn't. the same money would buy a hell of a lot of maps and a GPS
Find a 26 inch screen that can be folded up to the size of a map and I might be converted, well almost, its still technology (as is a GPS) and it can fail, temperatures affect batteries etc.
I think the further into technology with this stuff we get the more detached we become from understanding the basics, map, compass, pacing, timings etc.