Spoiler alert: the Glock 42 delivers all the performance you’d expect from a larger .380 ACP handgun, provided you use good ammo.
I mean, watch the video, the people at Shooting the Bull 410 go into detail, velocities, expansion, penetration and all that. More ballistics tests, including of the new/hilarious/awful/crazy/intense G2 Research RIP ammo, can be found on their YouTube channel.
But if you’re not an ammo junkie: the Glock 42 outshoots smaller .380s. (It would be interesting to see how it stacks against the SIG P250 in .380, there’s your comparison.)