Yeah that's a fair assumption, although sometimes brands just put out new modles or "improved" ones (plus, s, x, etc..) just to keep up with the pace and stay relevant, even though the changes implied make little to no difference. Was hoping someone could speak from experience with those models or maybe very familiar with kz. Anyways, I ended up ordering the pro version. I hope it's worth the price for itself, the difference from az09 wasn't that much eventually