Different sizes for 1/4, 3/8 and 1/2 inch size sockets
Conical holders prevent sticking, but allow tilting - Better than the normal ones when used stationary, worse when used in a drawer.
Can slide past each other when on neighbouring rails
No socket retention (Not necessary for non-mobile tool storage in my opinion, would therefore be needlessly complicated. Most good systems are probably also patented.)
Positioning completely flexible, not designed for any particular brand or model of socket
Rails
Three full rails per grid space
Can be tiled in any direction. Half rails on the edge form an additional rail on the seam between neighbouring rail tiles for more placement flexibility.
Very space efficient. Depending on nut size, you can reasonably get