An amazing piece of engineering

Admittedly I love mapping and maps, but the Garmin 76 is probably my all-time favorite electronic device. It is engineered and built extremely well -- very rugged and with an excellent user interface. Although I haven't used Magellens and other brands of handheld GPS units, I have used the Garmin 12XL that this is roughly modeled after. And I have used much more expensive DGPS Trimble units. Having gone over the same tracks and points with both the $8,000 Trimble unit and this $200 Garmin unit, my suggestion is not to bother with Trimble unless getting from 15 feet to 3 feet accuracy is really important to you.
I use this unit for mapping trails, stone walls, property boundaries, and particular points. And even under cover, the Garmin 76 will generally get within about 20 feet of the actual location if you sit on the point long enough to allow the unit to average out its satellite readings (~2 minutes). (This is the only complaint I have compared to the 12XL, which has a better waypoint averaging feature.) And the "breadcrumb trail" tracks that the unit collects is great for mapping trails, etc. These tracks are generally accurate within 50 feet.
There are some great third-party progams (such as "GarTrip") that allow easy uploading of GPS data into a computer. I use ArcView 3.3 GIS mapping program to handle GPS data, it works wonderfully with the Garmin 76, particularly with free third-party ArcView extensions such as "DNRGarmin." I can also upload points and tracks into the 76, but it doesn't handle as much data as the 76Map. To me the 76Map worth the extra cost, particularly because Garmin's maps aren't very detailed (1:250,000 I think), and Garmin's upload/download software is overpriced and underfeatured IMHO.
The screen is a great improvement over the grainy 12XL screen, and the multiple keys work perfectly. The case is very rugged, and battery life is decent (about 4 hours with 1300 mAh NiMh rechargeable batteries). The newer Garmin 72 may be just as good -- worth a look since it may be lower priced. The 76 is supposedly a "marine" GPS and it does have helpful marine oriented features, such as tides tables and a man-overboard button.
All-in-all, it is amazing what something the size of 2 cigarette packs can do!