When I took the concealed to carry handgun class the instructor also talked broadly about the .22 mag.
He said it was the most feared round by law enforcement officers.
He gave several occasions that the .22mag had pierced armored vest.
He stated that the vest would stop a .357 mag or a .44 mag but due to smaller bullet diameter that the .22mag went thru and told of many officers killed or wounded by them,as well as several civilans on cases he had investigated.
He also gave examples of the local DNR using them to kill deer for research studies.
He only gave those as examples and certainly did not recommend them for deer hunting.
He did however recommend them highly as a self protection handgun.

He is a conservation officer here in WV and certifies local state and federal law officers in handgun training,he has many awards and shooting records and is a no nonsence kink of guy.
I highly recommend him to anyone that wants to take the concealed to carry class to get their permit.
His name is Richard Robinson and can be contacted thru the wv Dept. of natural resources.