I am looking for a fish finder for my pontoon. Don't need anything too fancy..... just a reliable & accurate unit that locates fish & good bottom structure readings. After searching them over on several websites, I am about cross-eyed & was seeking a little help from others with their suggestions from what has worked well for them. I saw some had a picture of a fish, while others had a "curved line" (sorry for my lack of correct name). Is one better/easier to read than the other? I fish on freshwater lakes that usually are no deeper than 200'. Any help is appreciated.