I recently purchased a VERY lightly used Gen 4 G 19. I picked up 500 rounds of WWB ammo labeled 124 gr. NATO at the same time. (Had not seen that before BTW).
Anyway, I have had a good number of brass to head hits from it with this ammo. The ejection pattern is also all over the place. It is feeding reliably and the BTH doesn't really bother me, but it is odd. My G21 and XD9 SC never do this.