I did a quick review, I notice that the edges are rounded/smoothed, but no obviously uneven sides. The position of the painted numerals vary however, many of them are painted on off-center. This doesn't bother me, but it may bother some people.
As of this morning, my "1" is completely gone, and the "7" is starting to wear. For context, I carry it in a trouser pocket next to a mobile, but I make sure there are no keys/coins (to avoid scratching the mobile).