My favorite is the Old Bakersfield PD Qualification. It's only 10 shots but the last two are at 20 yards and there is one reload on the clock, meaning the disaster factor is very high. I use a paper dessert plate as the primary scoring zone stapled to either an IDPA or USPSA cardboard target. I can do it with everything from my 2" 940 to my Bowen Redhawk Alpine Conversion. 45 Colt with actually service grade loads. The Redhawk is most challenging with the HKS speedloaders. I know only one police officer who can pass this with his duty gun and he's a young SWAT operator. Most people I know won't even attempt to try it. The sight of a shot timer strikes fear into the hearts of most men.