Question Dual Monitor Arms: Side-by-side to stacked?

[oguruma]

I currently have a 34" ultrawide and a 27" 16:9 Monitor. I currently have the 27" on top of the 34" with a vertical/stacking monitor mount.

I'd like the ability to easily move the 27" to the side of the 34" (as in, on the same level) for when I need to do photo editing or video presentations (I much prefer to have the monitors side-by-side for those things).

Does anybody know of a quality monitor mount that will accommodate this?

 

[geofelt]

Ergotron makes top quality monitor mounts.
https://www.ergotron.com/en-us/products/mounts

Do you need a wall mount or a desk mount?