Down Imaging/GPS Finder Questions??

Hi, I am thinking about upgrading my trolling motor fish finder to one that includes down imaging. Right now I am running an older 5 series Humminbird and from what Ive been reading/seeing, a down imaging unit looks like it would be nice. I was looking at either the Hbird 581iHD GPS combo or the Hbird 561 DI. The main reason why I pam looking at these is price as I am a college student and won't have a ton of cash to drop on a real expensive one till this winter when I graduate. Would I be better off just waiting till next summer and getting a more expensive unit like an 8 series Hbird?? I was wondering if it not being a color screen is that big of a deal? From the pics that I have seen of them, its seems like the image is fairly clear even being black and white. My second question is it really that beneficial to have GPS at the bow as well as at the helm? Right now I have a Hbird 385 color gps finder at the helm with lake maps as well as a lowrance m52 gps finder that only deals with waypoints, no maps. I fish club tournaments as well as some open tournaments. Thanks for the help!!!

The best time to buy electronics for the boat is usually at the end of the open water season, when manufacturers drop their prices to get rid of inventory and make way for the new models. Lowrance had some great deals and rebates on their HDS units as they are now coming out with their touch screen models. Is color that big of a deal? Not really. I prefer the color units, but frankly color doesn't really give you anything you can't get from a black and white unit IMO. Just a preferece thing. Plus, the B&W units are less expensive than the color units. If you have a trolling motor up front and fish off the bow, a sonar/gps with lake maps combo is a must have. If you are just fishing a couple of lakes that you are already very familiar with then you would be fine with what you already have now. But if you like fishing different lakes and are fishing tourneys, a unit with built in maps makes sense. A common method is to use the electronics to slowly follow an underwater feature, such as a drop off or a reef. Having GPS with a good map makes this possible. There are some nice, entry-level priced HB and Lowrance DI units out there now. You should be able to find something that fits your budget.