Ive been around the jets a long time. I have lots of fishing friends that have them and I have a G3 1656 CCJ. It has a 60/40 yamaha jet. 60 horse powerhead that translates to 40 hp at the jet. They are a must have for rocky rivers and that's pretty much all I fish, or use to at least. I dont fish as much as i use to.

If you get one, get the absolute highest hp engine you can afford. They aren't as efficient as a prop driven boat. 2 strokes make a little more bottom end torque, but the newer 4 strokes like mine hold their own, and they're much easier and cheaper to maintain. Overall I like the 4 stroke for day in day out use.

They do suck stuff up but usually raising the trim up will clear the clog. If you're in a rocky river you usually dont have to worry about stuff getting in there and clogging it. Outboard jets are much easier to get unclogged that an inboard jet. If you get an inboard jet you will need to install what's called a stomp grate.

I used to fish a river the past couple of summers where I caught a limit of crappie when no one else could when the water was low. I had to pass over a shoal just had 6" of water over it in order to get to the deep holes.

Someone above mentioned putting a jet foot on your boat. It may work, but here are 2 reasons why it may not. 1) If you have a prop outboard on now, your current powerhead almost certainly wont be enough to handle the jets 33% reduction in power, and still push your boat or even get it on plane. 2) A jet requires a smooth transition of water from the hull to the jet foot. Laminar flow must be achieved to keep it from ventilation or cavitation. There must be no obstructions on the hull ahead of the jet foot, and the water coming off of the hull must be flat, not at a V like would be the case in a transom with a steep deadrise. For example, lifting strakes on a prop driven boat are placed in a manner that works best for them. Jet boats have a totally different setup to avoid what I just described. Another example, if your hull is a V hull or semi V, and that V goes all the way to the transom you can forget about running a jet, unless the deadrise is very very low at the transom. Even then you will have to hang your jet foot pretty low to get laminar flow and that would create alot of drag. Mine is a semi V at the bow and transitions to a zero degree deadrise at the transom, and it also has a 2" tunnel that allows me to run the motor above the bottom of the boat, making it where the motor is not the lowest hanging thing. Most true outboard jet boats have a tunnel hull.

Thats just scratching the surface, but should give you an idea. If you want to know anything else just let me know.