One notable difference I see is that the 'number approaching' warnings (graduated circles or whatever) are vertically centered between the two center rows of numbers on Fuji, whereas Kodak and Ilford have a set of indicators for each row of numbers. Even stranger, the lower set of numbers (for 6x9) has three rows, but the indicators are only on the bottom one. If there is no warning, it wouldn't be too difficult to cruise right past the number, especially if it's not lined up accurately.

I had scanned three popular backing papers a while back as part of some other topic. It appears Fuji gives the least info.