Paulo, you're right - they're not toys. They are highly sophisticated electronic devices that not only have made life a lot easier for most of the world, but additionally, made the world a lot safer.
Having worked with electronics since age 12, when I got my HAM radio license, which was 60 years ago, one of the things I notice most is the vast majority of individuals that purchase GPS/Plotter/Depth-Finder/HD-Radar combinations rarely pick up the instruction manual to learn how to operate the myriad of incredible features.
In many instances the operating manuals never come out of the Zip-Loc bag. The same individuals have never cracked the owners manuals for their cars, microwave ovens, Flat-screen TV, Smart Phone, etc... This is a shame, mainly because there is a wealth of great information at their fingertips, both with the devices and the manuals, and they're not taking full advantage of what the device has to offer. In fact, many owners of GPS/Plotters have no idea what the device can do other than display the charts and current position.
Someone posted above that sailors with these systems must spend a lot of time pushing buttons. In reality, that's not the case. Once the systems have been properly programmed, it's a "set it and forget it" scenario. After the initial programing, everything else is pretty much automatic. Like I said above, sit back, relax and enjoy the ride. In contrast, you're not constantly looking for things on a 2 X 3-foot paper chart, and staring at markers or buoys through your binoculars to try to determine your position. We've all been there, done that and got the tee
Granted, some of the owner/user manuals are horribly written, and some are nearly impossible for finding answers to simple questions. Fortunately, there are forums like this one where you can ask a question and usually find a viable solution. While it's not always the case, most of the time, at least at the Sailnet, it's the norm. Now, it may not be the answer you want to read, but then again, maybe it is.