As for what brand is better, that would be non of them.
All asus, or msi or gigabyte do is making plastic shrouds and a backlight for a panel they buy from samsung, lg or similar vendors that actually MAKE led panels.
But as for which has the best panel, that would be MSI.
All are 144hz 1080p, but the ASUS is a TN panel, the GIGABYTE is a VA panel, and the MSI is an IPS panel.
The gigabyte and msi have good color accuracy, but aren't very bright, while the asus is quite bright but it's colors aren't even listed, and the viewing angles are quite bad on anything but the MSI.