Omnigrid most definitely and if you can find/afford go for their Omnigrip range.
These have integral sandpaper dots which dont cover over a crucial measurement ....
like the 2 1/2" junction on my 6 1/2" ruler! D'OH!!
Creative grids ? Are they the ones with RED Markings???
My first ruler had red markings and I could never see them on the fabrics... Be Warned!