Is DownVu / ClearVu worth the extra $$$s?

 Got enough vouchers for the new GPS Sounder.  Thanks Santa.  Don't need anything spectacular as its only a 4.3m boat and I have 30 years of proven numbers from the area to use. Looking at the Garmin Striker 4 or 4dv.

Anybody that is using them or knows a bit about them, is the ClearVu / DownVu worth the extra $$$'s?