Hi and thanks for your question.
The fishfinder you are referring too is decent for the price. Lightweight, long battery life, water resistant and does not require mounting.
The 25 degree angle of the sonar is just about right for a float tube. Some people prefer a bit wider angle such as 45 degrees as you get a better reading when a school of fish is approaching rather than just be alerted when they are only directly under you.
Some of us tuber/tooner/ yakers will us a different type that does require minimal mounting but offers a wider angle and even side views on some models.
Of course, battery life is less to a higher wattage and the batteries are a different story.
While there is no perfect fishfinder out there to meet all of our needs, each person will learn to use what they have and use it to their advantage.
I personally use my fish finder more for finding depth, structure and water temp. Finding fish at a particular depth in the thermalcline will just give you an added advantage as to what depth you should be fishing for the species that your are targeting.
As I mentioned before, that unit seems to have the bells and whistles that you are looking for with the added convenience of being lightweight and low power consuming.
Feel free to give it a try and even a review of your opinion on that unit. That could help others into either buying one just like it or avoiding it to pursue something more of their own liking. Bass are toys. Gills and Trout are food. There is a fine line between fishing and standing on the shore looking like an Idiot Fast, Free Registration Tell them TubeN2 sent ya
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