Picked up an OZ9 a couple months ago. The OZ9 is a $1500 glock- actually, worse. I had to replace the Zev extractor with an OEM extractor to get it to function reliably. If you plan to shoot it in Production, then you're screwed on the reloads. There is no way to add a grip plug to the giant gap at the rear of the grip module.
For me, the modular frame was their biggest selling point, but they totally butchered the potential of this platform. On top of that, there are TWO different frame sizes with incompatible grip modules. Why??? Super disappointing...
EDIT: btw, due to these issues I ended up going with a Sig X5 Legion ($900)- best bang for the buck out of the box