Once you get on to them ( suggest downloading the Garmin simulator and practicing a couple of hours) they are gangbusters.
Great for IFR.
Different from the trimble thought process but once you learn how to access the file cabinet as I like to explain it ( how to access what where ) it is a wonderfull thing. Really not hard to get onto. If all else fails read the boring novel about that Manual guy.
Perhaps someone from the Air Ambulance in Ontario Canada will post. They have retrofitted their 76s over the last couple of years.