I have a 276C, that I upgraded from a GPS-V. I do like it. I added the largest memory card available. I have the City maps and Topo maps loaded on it; and I can choose which ones I want to view, as necessary.
If you intend to use it for traveling the world, it will be much more expensive than its purchase price. My City and Topo maps are for the USA (maybe North America); so I am covered for any place I intend to go in the next few years. For long trips, you may need to take the laptop, to load the necessary maps, as you go.
The auto-routing can be problematic. It has a few settings that can help improve its function. If you set it for "only right-hand turns", you may be given some strange routes. You can set it to priortise the street level it uses to get you from point A to point B.
The battery seems to last all day. The antenna works very well, and you can use an external antenna. It has voice directions, if you like that sort of thing (I don't use that function). It is built to take a beating. It is a little heavy for "lightweight" backpacking, but definitely good for backpacking.
It is actually a Chart Plotter, and therefore designed for nautical navigation. It has an input for a depth sounder, water temperature, etc. If you do any navigation of waterways, you will find this unit to be that much more useful (with the purchase of the nautical charts).
I have not found anything I like better, since I don't have space in my rig for a 500 series Lowrance Baja.