Airsoft pellets are plastic and so have lower sectional density than bullets, but otherwise I think the comparison is apt.
What is it about this silly little gun that keeps causing the media to discover it over and over? It's been floating around for years.
I shoot people with it every weekend, and noone has had it "penetrate to their heart" yet. Give. Me. A. Break.
The important question is how many of these could you carry concealed?