There are many excellent models with various features and in my opinion it boils down to BUDGET and NEEDED FEATURES. I have just finished setting up our new 27' Boston Whaler with dual Raymarine E-120 displays. These are large displays on an networked Raymarine platform which allow us to view SONAR (depth contours), chart plotter, RADAR and input video from U/W cameras and a gyro stabilized FLIR (both to be installed at a later date). The displays are bright and can be viewed easily in daylight conditions and because they are color, we can estimate bottom density when looking at the SONAR. This may be "overkill" in your area but if you are using side scan SONAR, you might consider some of these features. With a chart plotter you can run parallel searches in a systematic fashion with proper overlap and covering the entire search area. You already know the benefits of having a SONAR that looks straight down (so your tow fish won't strike the bottom as the contour rises). With this Raymarine system, you can "split" the display so half the screen is a chart plotter and the other half is SONAR. One of the other neat features is a SIRUS satellite receiver that allows you to monitor weather conditions from the national weather service. You can view the weather RADAR and other conditions that may be hazardous to your operation. Check out:
http://www.raymarine.com/raymarine/Default.asp?site=1&SECTion=2&Page=1007&Parent=2
Garmin has a system similar to the Raymarine previously described. While I went with the heavy duty Raymarine system for our department, for my personal boat I use the similar Garmin system. It is loaded with features too (Weather Service RADAR transmitted over the XM satellite system) and is less expensive. The display is a little smaller and the housing is plastic as opposed to the aluminum found on Raymarine. Check out:
<http://www.garmin.com/products/gpsmap3210/>
The other system I would give STRONG consideration to is the Humminbird 900 series system that incorporates a "cheap" side scan SONAR, bottom profiling and chart plotter. Information is available online at: <
http://www.humminbird.com/productlines_wide.asp?ID=614>
Lowrance makes excellent units too (as mentioned previously) and as you will find out, budget is going to be one of the primary factors when making a selection. Certainly, you can also go to Wal-Mart and get something that will tell you depth under the keel for $99, but then again, a weight with string wrapped around a Coke can will do that too!
Good luck with your selection! If you can advise as to your budget and what features you are looking for (what you hope to accomplish with your unit) I would be happy to offer a recommendation.
Blades
