[Old Man Dave]

I had the older version the Humminbird Dimension 3 on my boat for 10 years. It scanned at 45 degrees to each side of the boat and therefore showed a distance equal to the depth of water each side. So in 30 foot it showed the seabed 30 foot either side of the boat as you travelled along. Think it was rated 700+ watts rms or something like that and was a mono display not colour. The 250 foot scan is probably the scan width in 125 foot of water. I looked for wrecks and reefs and occasionally it was useful. However when it broke I replaced it with a dual frequency colour sounder rather than another 3D sonar. Overall I'd say they don't work well enough to justify the expense. That said mine was an older model so maybe the newer ones are better. It's mainly computing power that determines performance and that's come a long way in the lst 10 years.

Let us know hoe you get on.

Dave

PS what I'd really like to try is one of the FLES (forward looking echo sounder). They look as though they really reach out a fair distance. Remember the 3D shows you what you've already passed over. Think they're called Interphase or something.