Opinions for console unit... (2) 7" or (1) 9" MEGA+

[FishingKY]

The used boat I bought last year about this time came with Lowrance units and after using them for a year I'm debating going back to Humminbird. Currently there is a 7" HDS gen2 touch at the console. What are your all's thoughts on a single 9" or two 7" at the helm. I ask because I'm sure there is more to this than total screen size, such as rigging needs and issues, transducer usage and possible interference, etc..

Would be...
(2) Humminbird Helix 7 CHIRP MEGA SI GPS G3N
OR
(1) Humminbird Helix 9 CHIRP MEGA SI+ G3N Fish Finder/GPS Chartplotter

[Wayne P.]

If you get two Helix 7 G3N, one can be a SI model and one can be the CHIRP model and just the SI transducer has to be installed.
You would share sonar data to both units via Ethernet and they would perform as a single larger display with whatever views you choose to display on each=more display real estate.
You could use the included Dual Spectrum CHIRP transducer in the bilge for shoot-thru and connect it and the SI transducer to the display with the 9 M SIDB Y cable. Or you could exchange the transom 2D transducer for the shoot-thru version.

[Wayne P.]

The negative of the Helix 7 MEGA SI is it does not have dedicated Down Imaging, just composite DI created by blending the two SI pulses.
The Helix 9 MEGA SI+ has dedicated Down Imaging with a Down Imaging piezo in the SI transducer.

[FishingKY]

So on the 7 MEGA SI, without a dedicated Down Imaging, would the down images be better on the 9 MEGA SI+ and if so how much better? I have never used the DI but I could see it being extremely useful at locations such as Dale Hollow, Laurel Lake, and other offshore fishing locations where you are not pounding the banks.

[Wayne P.]

So on the 7 MEGA SI, without a dedicated Down Imaging, would the down images be better on the 9 MEGA SI+ and if so how much better? I have never used the DI but I could see it being extremely useful at locations such as Dale Hollow, Laurel Lake, and other offshore fishing locations where you are not pounding the banks.

Yes better. Single piezo images are sharper than blended piezo images, how much is subjective.
Plus the H9+ would have more Imaging depth capability using the MEGA frequency. 200' vs 125' spec.

Look at the specs for each model on the Humminbird website.