I'm looking at Fish Finders for my Kayak. I'm thinking of going with the Garmin 4CV or the 5CV. The 4CV would work if you only use one CHIRP or ClearVu at a time (since the screen is small). If you really need to look at them both to compare images, then I'd go with the 5CV. I've never used a FF before. I'm also not set on Garmin, but I want to keep the unit under $300 (the lower the better). Looking for insight on how to best use a FF on a kayak.