I have a Lowrance XOG. Pretty cool unit. It's primarily a car navigator, but can load lake maps into it (buy seperately - which almost all are). There are only 6-7 units that can be used as a car and boat navigator (at least last year when I did my research). The XOG is by far the least expensive. I'm sure the others are much nicer, but it does what it is supposed to do. The battery life is a bit low (2-3 hours), but I have mine plugged into the car or boat battery when in use. It wouldn't be a good choice for shore fishing or no access to a DC plug. But for less than $200, as compared to $400+ for the other models, it's not bad.
I'm sure there are some other great features in the others that this does not have (live traffic updates, FM transmitter instead of having to use and auxilary cable, and wifi would be nice additions, also the power plug covers the auxilary jack - need to use a cable with a 90 degree). The car navigation software isn't the best as well. It took me through Manhattan, instead of by passing, just because it appeared to be 5-10 minutes faster, which I sat in traffic for an additional hour or so, plus got rather broken signal in the tall buildings. Just like every GPS navigator, it doesn't know the "local" routes. So, I always turn mine off, if I know where I am.
I know from reviews, the Garmins (best, but pricey) are the easiest to use and have the best car navigating software (still need to add on the lake contour programs made by Garmin so limited options and an additional $100-$200). Garmin nuvi 500 is about $500, they also have some newer "cross over" versions that are $900+ which may have the maps loaded. Megellan has a crossover model that is around $400, with very limited lake maps available (made by Megellan). Lowrance has the most maps available, due to their years of experience in the marine chartplotters (XOG uses the same SD cards). The price and various options and availability of quality lake maps was my deciding factor on the XOG. You can find older (used) versions of Navionics Hot Maps or LEI Fishing Hot Spots for a lot less, that work just fine in the XOG but not the others. My entire setup - unit and map chip - was just over $200. It helps me when I am travelling for work, and keeps me on structure while fishing rather well. I also like the MP3 player, and use of standard SD cards. You can find 2GB SD cards for under $5 shipped.
FYI - I'd repost this thread in the off topic or even main board. It has more to do with fishing than 1/2 of the crap that is posted. I'm sure that you'd get a lot more info than on the for sale board.
post edited by Porktown - 2009/09/03 09:11:20