Scot: Nothing Perfect Pass does will emulate ZO to any great extent. The way the systems operate are so different that it is nearly impossible. That said, if you are chasing an identical feel boat to boat, it doesn't exist. We have two identical Nautiques (2007 & 2008) on my lake and each feels somewhat different. Therefore, I would recommend getting a slalom switch, set your PP to classic mode, KX minus and PX 10 or 15. This will give you a somewhat similar "feel" to ZO.  Otherwise, you'll be faced with the same decision I made in August - upgrade.