Quicksort dual pivot or single
Basically Dual-pivot Quicksort buys you two items:
The best case running time is $\Theta(n \log_3 n)$ instead of $\Theta(n \log_2 n)$ since each partition is the third part of the entire current range. Also, if one pivot is not good (it is close to one of the ends of the current range), there is a good chance that the second pivot will be better.