Re: FF under $200
three most important features in a fishfinder: resolution, resolution and resolution. get the most vertical pixels per inch you can afford.
Eagle fishmark 320, best value for the $$ IMHO...basically the same unit as the x96 only $65 less. anything less is useful for reporting depth and water temp, maybe contour, but that's about it.
Also, I find the zoom in/zoom out feature to be extremely helpful. In freshwater 20 - 50 ft or so.