From someone that does a 3x2 setup I'll add one downside: on my split setup I run the bottom row 90 degrees from the desk while the upper ones are angled down and slightly so that both are viewed straight on when glanced at. Not having a physical split like this makes it so the top and bottom will always seem angled.

I suppose if it were curved it'd solve that problem but then it would come with assumptions about how far away you sit and create new problems like glare streaks.