The meanest bullet doesn't make up for lack of marksmanship.
I was a LE firearms instructor for alomost 30 years and during that period of time I got to try a variety of ammunition. When I worked for a municipal police department the chief bought the cheapest duty ammunition he could find.
I worked for the Federal goverment and there they kind of rotated their purchases between the major manufacturers so I got to try everyone's ammo. Some expanded better and some penetrated better. I looked for reliabilty and accuracy and after that I wasn't interested too much in expansion. I liked the early WW subsonics in 9mm. Yes they didn't expand well but I found them phenomenally accurate in the S&W autos we carried. I realize to most the accuracy thing is not an issue as they don't shoot that good.
Jim Cirillo, veteran of NYPD stakeout squad, survivor of several gunfights, and pistolero extrodnaire still is in his quest for the perfect bullet and hasn't found it yet.
Just my take.
Just my take.