[swarm]

It's worth the money, I question the validity of it's 6max rankings, the few sets of rules out there to implement are suspect.

The best part is analyzing your aggression level, position where you are winning and losing money, and what hands you are winning and losing at. You can certainly find and fix leaks quite easily by routinely looking through it.

Keeping notes on other players is indeed a necessary tool as you move up stakes as well.