The S&W M&P 15-22P is a blast to burn ammo through. I know it truly isn't a traditional handgun, even though it is a pistol, but man it is fun!
As for more traditional ones, I really like the Sig P238 SS. One hand, two hands, left, right, whatever...Very cool .380.
As for power, along with accuracy, the SW .44 Mag revolver 3". Once you get used to the blow back, it's pretty neato.