Does that extra speed and penetration = better though?
In a .22 caliber weapon I would have to say yes, I can't see any advantage to .22 mag over 5.7, to get closer to the performance as the 5.7 pistol you would need to carry a .22 mag rifle, which pretty much ends the comparison, and even though they aren't all that common, there are 55 grain loads for the 5.7, nothing like that for the .22 mag.
Or would a somewhat "slower" Hollowpoint .22 mag be more effective at creating a bigger wound channel and energy dump INTO the target, rather than through the target...
Doubt it, mainly because .22 mag is generally designed as a pest control caliber isn't it? I think 50 grain is about the highest weight you can get out of a .22 mag, and from what I've read in a .22 mag review in Gun Tests (using rifles) the 50 grain load they tested seemed to be past the tipping point for the caliber, seems like the 40 and 30 grainers are where it's at for the .22 mag. I'm pretty sure the .22 mag is mainly used for the same game uses as .22 LR, just with longer range and the ability to be used on larger pests like coyotes if you like.
The 5.7 is designed primarily as an anti-personnel round, even though it can do really well as a pest control and varmint round too. It's got bullets available that are better for penetration, better for use against people, and it is better suited to launching the somewhat heavier bullets that the .22 mag starts to lag badly with.
I don't own either caliber, but that is what I've taken from what I've read. I read a lot, it isn't the same as shooting people with both, but there it is.
