No doubt about it The si unit!!!! That will help you find and catch fish. You can have a cheap trolling motor to do the job!!! Actually let me back up on my statement........ Are you only allowed to get one of the small si graphs??? If so you better have some great eyeballs to see things your looking for on the smaller si units. 1197 or hds8 versus I-pilot..... I would do a graph. hds5 or 797 si versus i-pilot. I might go with the i-pilot. Get a big graph if the wifey will let ya!!!!!!! It is by far and away the best tool on my boat. Ive only had it on the water a handful of times but when you find structure with fish stacked all around it you will be ecstatic!!! I have the terrova with I pilot also and it is a heck of a tool also BUT it doesnt help me find fish!!