I havn't run a jet in a few years however I have caught hundreds of eyes using them. There are truely so many variables it is tough knowing your exact depth. You will find when you catch a fish at a determined amount of line let out, ie 125 ft, that will be your kill zone. What I like to optimize depth is using a good braid, 17 lb test or so, and a stoudt rod. Braid doesn't have the stretch and a stoudt rod keeps the jet digging rather than the rod giving way to the jet.