The H0WO524163 that i got a few days ago is indeed slightly different than other HOWs that i have seen. Today i got HOW3291901, HOW3422628, HOW8806630. These 3 notes appear to have a different paper composition than that of HOW0524163, that same note was very hard to rip. I did try but didn't tear it. On the other hand the three HOWs found today ripped easily with little effort, so yes indeed i will agree that HOW notes in the 0.52-0.54 range are different!