I didn't really think I would use the GPS all that much at first, but now that I have it I will never go without.
Unless you fish tourneys and fish alot of new lakes, the gps without the mapping feature on the Matrix 17 will do just fine. I couldn't justify spending the extra cash for the outline of the lake and contour lines, that's why I chose the 37.
You will be able to save more waypoints, and tracks than you will ever need. It is very accurate. And also simple to use.
Plus with the PC connection cable, keeping track of everything on your computer is a snap.
Also... board member Greg Walters, who works for Humminbird and hangs out here, just loves when you ask him tons of questions..
I started with that set up. It works great. I agree with Steve in getting the PC cable to keep track of everything. If you are a troller, it will improve your efficiency when you start marking and reproducing the productive paths.
I'm with Steve anD Rich, I have the Matrix 77c with the GPS and the PC Cable, it is GREAT!! I downloaded all the GPS locations on my lake for the DNR fish attractors into the PC, then downloaded them into the Matrix unit and off I went! I've also marked humps, brush piles and other landmarks (like the ramps for foggy days!!).
Every once in a while, when the kids, wife and a friend want to go fishing I wonder - MAN I should have bought the Bass Buggy!! but then 90% of the time its me, or me and 2 people and it all works out.