most use High Low
I'd say 60% of players use High Low and the other 40% use KO, Zen, AO2, Halves, or some other count. Hopefully you are side counting Aces because Hi-Opt 1 is weak without it. You won't win much more switching but if playing deeply dealt pitch games Zen, Hi-Opt II, or AO-2 will win about 10-15% more than Hi-Opt 1. Hi-Opt 1 with Aces is just marginally better than High-Low in deeply dealt games but that Ace side count, easy for single and double deck, gets more difficult to maintain for shoes.
High Low is the industry standard.