Here is my Portrait/Landscape/Portrait setup using the Ergotron LX Triple display lift.
The center landscape display is an LG 29EA73 and the 2 side displays are LG 24EC53s.
My desktop is extended across all three monitors using Eyefinity.
The setup from left to right is 1080x1920 (portrait), 2560x1080 (landscape), and 1080x1920 (portrait flipped).
Because the center monitor is so wide (21:9), I had use an Ergotron Quick Release bracket with spacers.
The mounts for the 2 side displays are on the very end of the horizontal mounting arm.
The weight of all three monitors is just over 25lbs which is on the extreme low end of the recommended weight range.
After I made a big adjustment to the lift pressure, the simultaneous lift worked great.