One of the drills I like to run at the range, that I saw at STG's Warrior Pistol class was the hostage head-shot drill, the target is actually developed by Paul Howe, I bought them from LEtargets.com.
That was a 6.6x sec run, which was not clean I threw one round into the white. My friend and I shot these drills four times each and it is easy to get addicted to them. I am in the low 7 seconds clean, which needs a little bit of work. Why is this drill cool? Aside from the pew-pew-pew factor, it does a good at making the person shooting transition and tempo-change. Good for diagnostics as well. Run at 7 yards, from concealment.