I've had most key technology released Garmin GPS units from the early days and have tried others but always switched back to Garmin as my favorite device of the time. My current Garmin was state of the art years ago as a first voice command offering in large ultra thin format. Sadly it has recently lost voice capability so I'm now considering more RV specific choices and quite drawn to the
Rand McNally's RV Tablet 80.
For the Garmin ... LM Lifetime Maps is a key choice that pays for itself in just one years update typically. I've not had much use for the T in LMT as I seldom travel in cities where Traffic is available (especially with RV).
Years ago I had a couple Magellan GPS units that didn't make me happy with so it's hard for me to give one of their current offerings another look.