I fully agree with Dave's post (above) in every respect. Get the car kit. I use it more than the flying mode, but that's because I don't fly that much - yet. It can take you to a specific address anywhere the MapSource software covers. Mapsource is the computer program (on your computer) that allows you to download detailed maps of areas of the country. It is part of the "auto Kit".
The 128 MB card that comes with the auto kit holds enough data to cover detailed road information for the entire auto route from NE Ohio to S-n-F, or from NE OHio to Denver via I70, or several states in you area. IT'S AWESOME. I can't imagine how Garmin does it! To change the memory card info, plug your GPS w/cable (supplied with the kit) into a USB port, bring up MapSource, select the areas on the map to download, a couple of clicks and Garmin does the rest.
You can upload and download routes, waypoints, to and from the GPS. You can add hundres of your own waypoints. Be sure to upload them to your MapSource (computer) before updating your GPS software. They are all wiped out with a new update!
Another thing, Garmin has a FREE Log book to install on the computer for you to upload you flights that are recorded on the GPS each time you fly -- Awesome! T.O. time, airport, TE, destination, and a bunch of other data.
The auto functions no way detract from or interfere with the aviation functions or vice-versa with respect to memory usage or anything else I have noticed.
Don't forget the FREE Garmin software downloads (not aviation database) for the 296 (and other models) and MapSource. The latest software version for the 296 is 3.70. If you buy one, it would be interesting to see what it has. You will find it on the very first screen after turn-on, bottom right hand corner. Doesn't matter much because if you buy the auto kit you can update it easily. (Maybe you can update it without the auto kit, too, if USB the cable is included.)
http://www.garmin.com/support/download.jsp
A single aviatioin database udate (Jeppesen) is about $35 (credit card on line) or you can get other update options online -- no need to send a chip in to Garmin. One free aviation update is included when you buy the GPS.
I have not been disappointed when viewing in direct sunlight. Looks okay to me. If ther is a reflection, just move it.
If you don't need weather, and other fancy things for the 396, I think this is the way to go.
I'm planning to put a RAM mount on the panel of my 7A so I can angle the GPS any direction. It is cool to have it IN the panel, but not very practical.
I love my 296. I'm sold on it. Can you tell?
(I've tried the Lowrance and have had at least 4 other models of Garmin over the years. Garmin is the best in my opinion.)
Don Gray
N17QB 7A in progress
Cortland, OH