We tested them in 4 different machines, and didn't have any problems.
But...if you're going to file it down to make it work, the notch isn't the best place to do it. File the front of
the card, to make it shorter. And don't go nuts and file it too much.
(iirc, 50 strokes on 100 grit sandpaper => ~.0001 inch. It shouldn't take much. Just make sure you don't skew the front of the card.)