The title says it fits monitors up to 25" but the description says 24". Which is correct?

it will do 25" monitors bit you only have like a 15 degree angle at most. your biggest concern will be weight and mounting to a good solid surface

I only have 3 monitors but may upgrade to a 4th someday. If I do not use the lower middle monitor stand, will the arms adjust enough to put the two lower monitors together?

yes they will, i will say my set up is 3 identical monitors across the bottom and 1 ultra wide 21:9 monitor up top. make sure to tighten all of of the moving joints. because of the fact my left armature swings forward until it was tightened

Questions & Answers: VIVO Quad Monitor Heavy Duty Desk Mount 3 + 1, Holds Computer Screens up to 24"

(1)

double click image to zoom in

Top Rated Visit VIVO Store

VIVO Quad Monitor Heavy Duty Desk Mount 3 + 1, Holds Computer Screens up to 24"

Fits up to 24" Screens: This quad mount holds four screens up to 24" and 17.6 lbs each with 75x75mm and 100x100mm VESA mounting holes
Full Motion: +45° to -45° tilt, 360° swivel, 360° rotation, plus height adjustability for optimal viewing angles
Measurements: The center pole's height measures 32". The distance between the two outside mounting brackets measures 52.3" when fully extended
Cable Management: An integrated cable management system keeps cords organized to give your workspace a clean appearance
Drill-Free Mounting: This product secures to your surface of choice up to 3.25" thick via a heavy-duty C-clamp, or use the equally sturdy optional grommet mount to suit your preferred layout

$79^.99 –