When???

[Bduck]

 Raymarine units are also nice, but are designed more for the salt water and extreme depths, ranges, etc.  

Not all Raymarine units are for salt water with recent developments. The first one I had was the A57D, it was suited for both fresh & salt water. I found it was little difficult to operate settings when the need to make changes on the water occurred. Next, the Dragonfly combo unit was a freshwater unit I used for about 5yrs. This unit I still have set up on my boat but using it mainly for GPS now. It is also a portable unit for ice fishing which an ice fishing kit consisting of a carry pouch with a battery & ice-ducer is available for purchase. This unit would a great on small vessels as toons, kayaks which comes in a couple of sizes with the 7" screen is as large as it comes, it has downscan along with sonar, simple operation. The main unit I'm now running is the Element HV 9" designed more for freshwater fishing. It was developed with some features from Raymarine's Axiom unit that is a salt unit. I like the Element for its features and simple operation to setup. A down/sidescan unit that also has a ice fishing kit separately available. Not yet ready to replace but keeping watch on the future and I also wait till the unit has been on the market for a while.