The differences he states in the advertisement are on the order of 0.2% of equity. If you can perfectly estimate each of your opponent’s hand ranges, then this may affect your ROI. But for most players not named Negreanu, opponent hand range errors will have a much greater effect on ROI.
That said, once SW2 is officially released the top 2 new features on my plate are adding customized opponent hand rankings and calculating ties exactly.
Also, remember that a SitNGo Wizard license is a one time purchase (all updates, including SW2, are free). Icmizer requires a monthly subscription fee forever.