I seen a guy at laguna with one like that on his float tube.Looked pretty slick,if its the one I seen the best thing is it runs on AA batts instaed of putting the extra weihgt in your tube with big regular 12v.I havent tried one myself but it seemed to be the ticket for a tube.I have rigged up my regular humminbird before on my tube and the battery was heavey and took up too much precious space.
But if your just pluggin along the shore I would rather keep it simple and as light as possible.Backpack and pole,just dont forget the camera and scale,and extra batterys for the camera.Just in case.Tight lines,
Billy.