HB 798ci hd combo .....then you have it all..... why just get down imging ...when for another $250-300 you have it all,maps ,gps ,down and side imaging ....the 597 would be good for front of the boat ,but if had to get one it would be 798ci combo .....I seen a pic of a man under water ,you could see his body and air bubbles ....cool stuff ...have found some on line for around $850.00 ... getting mine after x-mas