KO can definitely still "get the money", although single deck is the last game where folks say that using a fancier count can result in a measurable increase in advantage.
You might want to compare and contrast KO-P to reKO for single deck, and see how you like the differences in index construction:
http://www.qfit.com/REKOStrategy.htm
I've only played a little bit of single deck, so I'm really not the authority. I did use KO while I was doing it, though.