I have a hummingbird 787C2i on my console. I like having the lake maps downloaded into the unit and the capabilty to store waypoints. If you read the electronics section you can see the complaints against hummingbird and it's slow scrolling. This allows for a slight discrepency in what your seeing on the graph vs. what you are actually over.
All that being said, I've still been able to use the hummingbird to catch more fish by following the map contours.
For accuracy, I hear the Garmin's are hard to beat. I'd look at a low end Garmin. Black and white versions obviously are cheaper. But if you can afford it, get a color unit. You will not regret spending the x-tra money. Good luck.