After much research I purchased the Echomap 50s. I primarily boat on lakes and rivers with an occasional trip to the Outer Banks. When I bought this unit I did not plan on buying a g2 Vision chart. But, after reviewing the current rebate. I would get $200 back and I found the g2 map on Amazon for $180 delivered. So basiclly a $20 discount + a extra map.
I took a 900 mile trip right after purchasing. The unit worked great. I am very happy with the performance. The menus are simple to navigate. On my trip I traveled on the Cumberland & Tennessee Rivers. The depth accuracy was very good. There was a narrow section on the Tennessee river (near Clifton, TN) where the map was not correct, it showed me running on the ground. The rest of the trip it was spot on.