Fish Finder Opinions

I used to buy high dollar fish finders but salt water will zap even the best of them so now I buy all my electronics off ebay. I know a guy who is a big weenie at raytheon and he gave me one of the state of the art super duper super man fish finders with all the goodies including temp , speed, penis enhancer etc and in less than a year I managed to fry it..On the other hand I have a basic $59 dollar lowrance on my old 17 Mako that has worked without a problem for 5 years and it sits out in the weather full time.... .Frank