I think I remember seeing from one of your other posts that you play SNGs - if you want to play SNGs seriously, then SNG Wiz or SNGPT (I probably pick Wiz since it has a bit more functionality) is a must.

The other thing about Pokertracker is that you need it for the heads-up display software (Gametime+ or PAHUD) that can display opps' stats on the table as you play.