How does Blackmagic RMA process look like?

Last month I bought my first 4K BM camera. I suffered with obvious Fixed Pattern Noise, even at iso 200. I am not a purist, but it was too heavy, would be visible in theaters even for a layman. Grading FPN footage only makes things worse. They saw the captured stills, they said to send the camera back for replacement, this time checked by technican first. Nice and clean customer support, by email. But it took time.

I had a tight schedule of test shots coming, with light octocopter prepared for this camera model. This is theatrical 4k, full-feature production. Because of time and costs, I could not instantly switch to RED or any other alternatives (GH4 is not here yet). So I had to buy another BM 4K camera... I was lucky, this one was clean. No FPN.

Test shots went good: The clean camera model (S/N 1788506) shoots beautiful 4k, can be cut with RED epic footage in editing room. Meanwhile my 1st cam replacement came back. Foil, RMA red round stick on the box (serial number 1815090). I run the camera and I see FPN again - worse than in the first time, clearly visible on the camera screen. Could not believe this. I clearly can see the differences - my other camera is perfectly clean (except iso 800, I can stand it), but the new RMA is faulty, again.

So now I have two 4k BM cameras. Tomorrow, the faulty one (#1815090) is going away for another replacement to UK, it takes money, it takes time.

But my question is - how it is possible for BM technicans in UK to send back another faulty piece (with the same issue!). Do they check it for real, as they claim in their RMA emails? Or just changing incoming faulty piece with another random box, counting that this time it will be okay?

I am waiting for my 2nd replacement. If FPN or other new issue is going to happen again - which now I believe is quite possible, it would be an absurd. I've never experienced double or triple RMA in my 20 years of hardware buying history.

If you are hesitating to buy or not 4K from Blackmagic - wait for one year from now. Maybe something will get better in the company or some firmware updates will change their cams from beta to final models. Right now you'll get a beta version of the camera.

I won't mention lack of RAW recording or black hole sun syndrome, issues which are somehow accepted by BM community. Again: Too bad that such a great 4k camera suffers from such stupid reasons.