I dont even use my sounder in creeks anymore, and works really well in coral country up to around 15-20m and the sidescan picks out small rocks to big bommies anywhere up to 18m away before it tapers off. The shadows on objects really help determine where things/fish are in the water column.

Out wide the downscan imaging isn't helpful but still picks up baitballs either side.

Couldn't imagine life with it for shallow waters now hey!!!!

As that's the unit I have.

Great unit but obvious limits with side/structure scan.

Side scan/structure scan really opens up new habitat.

This newish technology imo is the go. One day all sounders will carry this.

cheers fellas, 

Dicko, what is the deepest you've used it effectively? Reckon it would still go to 30m? Also does the tranny plug straight into the back of the HDS or it the "box" required?

I suspect the humminbird and lowrance have similar capabilities, so can give my thoughts on the humminbird one at least to see if the feature would be useful. I ended up getting mine after seeing Damos.

I actually use mine heaps. Although its pretty cool at looking at rockwalls and whatnot, but I find it really useful for understanding what structure is like. The downscan is pretty useful for differentiating bottom. E.g. Whether its smooth on the cross section. Easy to see if its sand, weed, smoothish reef or rougher reef.

The sidescan allows you to find underwater structures really easy. I can figure out of the reef I went over is a lump or a finger. I can see the overhangs on the sounder and know if its worth diving. Have found sandy channels between reef when I was looking for KG's. I know if a bombie is isolated, or what its shape is. I can figure out whether I hit the main part of the lump or just sliced the edge. You can find dropoffs that are mostly parallel to the boat, find reef lines. See if the reef drops straight to the sand or likely has a ledge. Shows you how much weed there is to sand, etc. Its great if you make sure to use it. I've heard of a lot of people who say its not much use, but I wonder if they use it right (or have it set up right).

Its seriously awesome for finding dive sites where you want to get a good idea of a map of the area. I would imagine it pretty good for fishing creeks two where you could find underwater logs, or little underwater channels that havent appeared with the falling tide yet. I'd be surprised if it couldnt pick up big fish like a GT if it was close by the boat, but mainly its for finding structure. I've found it a super useful tool (just make sure the transducer is set up right, you understand what you're looking at and get into the habit of using it). At the moment, I have to drop off the plane to see the bottom easilly (can still see just below the boat but lotsa noise) though, so hard to find ground while planing. I do wonder if I reset the tranny if it will work better. Lowrance have a diff transducer setup though (and apparently you need a big box to go with it)

Sounds like it might be the go for finding dive lumps Tim. You get one and I`ll check it out before I get one ;-)

The down scan and side imaging is only good for slow speeds (<14kms) and calmer water as it says in the manual. This is simply a matter of power. It's takes a load of power to send the sonar signal and a load to analysis the information so given the units size it has implications for speed. This will be the same for Lowrance or any unit giving its size. Humminbird have better pixels so better image on screen than Lowrance (just the facts).

Like any sounder you have to understand the basic like how sonars work, signal strenght, range and reflection, and most of all turbidity. The good thing about Humminbird is that it has menu setting for different water types (fresh, shallow and deep saltwater) so it aids using sensitivity.

The key criteria for sounders is frequency and if you understand how different frequences operate then you will understand the inherent pros and cons of sounders regardless of brand. This equates to a higher frequency = greater resolution but less depth and a low frequency = low resolution but greater depth. This means when a 2D sounder is used a lower frequency produces a greater cone of circumference over ground as depth increases. Side scan just adds the extra dimension of perpendicual imaging instead of the tradional vertical of the 2D sounder. This means 180 degress of sonar from the transducer, not 20 or 60 degress below the boat (depending on frequency). Understand that and you will soon see the implications and possibities side/structure scan will add to your fishing environment. 

All deckies on my boat have been blown away with the side imaging/down scan (one pass of the Lena (boat dive wreck off Bunghole) showed the true potential of the unit and it would show the skippy and Sambo's holding on the boat)

The side/structure scan  jsut really shows up structure and habitiat as Matt says. 

Regardless of Brand (and I choose Humminbird for a few reason but waited a few years for the technology to prove itself and then saw first hand a metes unit bream fishing) they work better than anything within the boundaries of their design. Given the price don't know why so few have them.

I had the best picture of a croc on the Vic River on side scan. Likewise one could sit in the middle of the Blackwood River and scan the whole river, what other unit can do that? It's that good you can pick individual rocks on the bottom. Cruising rivers here in the Kimberley I can scan so much water that would otherwise take me 10 times more time using a traditional 2D sounder. That means less time sounding which means more time fishing and which structure has the best potential for holding fish.

Definitely recommend getting in a boat with one and see what you reckon