VIVO Dual Monitor Desk Mount, Heavy Duty Fully Adjustable Steel Stand, Holds 2 Computer Screens up to 30 inches and Max 22lbs Each, Black, STAND-V002 on Amazon. $35.
VIVO Dual Monitor Desk Mount, Heavy Duty Fully Adjustable Steel Stand, Holds 2 Computer Screens up to 30 inches and Max 22lbs Each, Black, STAND-V002 on Amazon. $35.
I really don't see how it can be more or less stabile than two separate single mounts. You attach the vertical post to your desk and the cross bar that supports the monitors is a single piece with a pretty hefty set screw. I have both the dual mount (in my wife's workspace) and the single mount (in my workspace), and I honestly don't see any difference in terms of stability. Just set it up and you're good. I have checked the set screws several times to see if they have loosened, and have always found them to remain secure.
I prefer two separate single-mount VESA arms, personally. I feel like it gives me more flexibility on where I attach them to the desk and what angles/heights I adjust them to.