I have owned 3 of these over the past 2 years since my initial purchase. I now own none after having finally given up on the product and the customer service and thrown the latest iteration of the product in the trash.
While the product is designed to be intuitive and user-friendly, it just plain doesn't work. It appears to be easily confused by thermocline and underwater vegetation. The programming of the unit does not allow it to sort the difference between thermocline, vegetation, and fish. In addition, the icon-based fish-and-rock display does not allow the user to get around this by interpreting a "real" image.
As they were getting some complaints about this, the company responded by changing the program and sending me a new unit. It seemed to show some improvement, depending on water clarity, but, alas, stopped working on the first outing. Then they replaced it with unit number 3, a refurb programmed to display depth and temperature in metric units. It seemed to show some hope of working so I...

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The Garmin 240 is an excellent value. It is your best bet for under 300.00. It is extremely easy to install, only a one cable hook up. The High Resolution display is top of the line. The display of the thermocline is great when it works. The transducer has given me problems. But overall it is an awesome value.

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With a limited budget, I shopped this one carefully, and the MAX 20 is the most bang-for-the buck I could find. The swivel base alone is worth the upgrade over the 10 or 15 models, and the better resolution only adds to an already great unit. Mounting directions were clear, and installation was done with common hand tools. The simulation setting allows you to see how it will work on the water. Never knew I what I was missing until I added a fishfinder to the old Lund. Highly recommended!

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When I used this fishfinder for the first time, I was somewhat disapointed. I usually fish from the boat in depths of between 18 - 25m, so I did when using the fishfinder for the first time. I ancored my boat in a depth of 20m and then cast the RSS into the water. However, the display did not show me the ground, it only showed 0.0m, there were a little bit of waves but only about 10cm, moving closer to the shore, the FishFinder started working at a depth of 17m. Therefore do not expect the Fishfinder to work at depths up to 100ft (30m) unless the water is flat as a mirror.

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