If you going to be using spit screen or multiple displays most of time, I would go with 2 9s. Approximate screen size of 9" screen in 9x6. So you get a total of 108 square inches of screen with 2 9s. The approximate screen size of a 12 is 12x8. You get 96 square inches of screen. So you get more real estate with 2 9s. Also if 1 goes out or has issues you always have a backup.
For side imaging you can put 1 screen with left side and 1 screen with right. If you want one large screen for DI display then 12.
Just the things that I would be thinking about with this purchase. Either way I am sure the new set up you choose will be great.

It depends on your use case and which brand(s) you go with.
Some units are good at specific things and weak on others.
Research what the "must haves" are such as side imaging, maps, networking, etc. With two units at the console you can run all side imaging on one and run side imaging on the other.
I think its gives you more options on what you display especially when you use a unit for engine info and mapping.
For example Helix units cannot display NMEA screens in a split screen with maps.

I prefer two units at the bow for the same reason.

I have an HDS 5 and HDS 7 at the console. I have been on boats with a single 9", and I much prefer having two separate screens. I run graph on one and structure scan on the other. Works well for me.

Helix is my only experience. 9” is tiny. Buy one 12” now one later. The g3 units and sides can a solid 90’ out in 10’ of water. That’s a lot to look at on a 9”.

If you looking at buying g2 helix the 9” has way less pixels and resolution than a 10 or 12.

The problem with two 9’s is the resolution of the 9 is the same as a 7. Horrible for detail. The 12 has much higher resolution, so it is the better choice for the console. Regardless. Resolution is king with side scan.

My Hummingbird helix 12 is enormous. Thats more then plenty.

If you do go for 2 then it should be two 10s not the 9. The reason is the 9 and 10 total unit size are the same but the 10 has more screen and higher resolution and the unit takes up the same physical space. I have a 10 on my bow and a 12 on the console. I could have gone 10 at the console and been happy enough but I really enjoy the 12. I run SI across the top of the screen and 2d/di split on the bottom and that setup gives a pretty good maximum view of all 3.

2 screens. If one goes down or starts acting strange, you’ve got another as a back up
One screen=all eggs in one basket

I have a 10" at the console and at the bow.

I am thinking about swapping them to 12" in the future!

Thanks for all the comments guys. I have decided on one 15” HB Solix.l at the console.

I looked at solix a lot, the thing I dont like besides all the issues they seem to have and the extra power they draw is you cant easily change the waypoint icon like on a helix. you have to go thru several screens to change it, where a helix I can tap mark, down down and then go right or left and scroll thru the waypoint icons and choose a rock tree log car fish etc. and hit save

Good choice. I went with a Carbon 16. Only cause I don’t like the clutter and everything on one screen.

Im running 2 10’s on the console and would never go back to just one.

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