The subsonic thing mostly affects the sound down range. Behind the
barrel you don't hear much of the crack but you get all of the gun
noise. 22rf drops below super sonic pretty fast anyway, particularly
out of a hand gun.
I have a couple bricks and they seem very quiet in an unsupressed
rifle. They make up for the low speed with more weight to maintain
down range performance.
I have tried it. I was disappointed with its accuracy and my observation
that it left a lot more crud behind than the CCI Standard Velocity
rounds. Further, sometimes it failed to cycle both my Ruger pistol and
S&W AR 15/22. The CCI rounds never seem to fail to cycle, and they are
plenty accurate.