As of a recent Selftest we have run, KACRs Detection Methodes can only be topped by Null AC, Hotguard or Cows Private Plugins.
SMAC is pretty outdated in my Opinion, [email protected]
Ultra instead is more up to date and can propably also beat KACR in the Opinion of Detection Accuracy.
To come back to the main Topic, KACR is Failsafe, ive never had any false Positives with the recent Version on my Test Networks.
If you continue to have false positives, try the new Action System on the Beta Branch which allows you to choose what is supposed to happen upon an Cheat is detected(like kick/ban/call admin/report/etc.). This Way you can properly Debug your Problem.