Greg,
I bought my bundle through Consumers Marine on the internet. Pretty good prices and no sales tax...1-800-332-2628.
I installed the unit myself, and while I'm pretty handy, there are enough boxes and antennas that it was a fairly involved project. The hardest part is simply firguring out where to place each component, and how you'll run wiring between boxes. You'll also want to keep the appropriate distances between your new GPS and Satellite antennas and the already installed VHF and radar antennas. That "mental engineering" will take some time, but once you figure out your particular installation it goes pretty quickly. The result is definitely worth the time and effort.
I would suggest that you look at the Garmin website to explore the available display modes and functions. You can also download or view the owners manuals and installation manuals without charge.
My only criticism of the bundle is that each box requires it's own power supply....so you're running wires to a terminal board for each box, as well as it's associated "data" cable to the network port expander. It would be nicer if Garmin incorporated the power wires into the data cable, but maybe this wasn't feasable because of the potential for electrical interference with data signals....
I haven't yet connected the depth sounder module...primarily because I already have 3 sounders installed by the previous owner, and I'm concerned about "interference" between four sounding units...(one unit picking up the return signal from another...) so I have to figure out which transducer location is best (there are limited choices now)...and will likely remove one of the older depth sounders.
I believe that West Marine also carries the Garmin 3210C Network, where you may be able to see the units in person and get some idea of their size and display capability.
Best of luck!
Dave