Poker Tracker

Ok I still consider myself a newbie to hold-em (been playing a little over a year) but I have now won consistently enough that I have a bankroll allowing me to play pretty much whatever I want to. I very much believe that the only way to improve is to play a lot. However, lately I have been requesting my hand histories and looking over them and have plugged up quite a few leaks in my game. My question is how valuable do you all think it is to invest in Poker Tracker (or similar software)? And what do all the stats mean?

Its great, for jeffreys guide to poker tracker go here. The most useful feature for me is using gametime+ to project everyones stats on the table, easy to lay down QQ when someone raises for the first time in 400 hands, and it's only $55 so if it wins you one big pot it's paid for itself.

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