I agree with Alex (because who wouldn't!) and while I struggled to pick it in side by side shots from different dives at the same site, I know my local dive sites and I prefer the photos with the retras. The retras gave me completely different (better) light quality from the first dive there, even with strobe positioning all wrong and backscatter through the shots. The colours are better and the hotspots/throw/eveness was nicer.
Some of my negatives are teething issues that I will get used to. I just hope the reliability is there, because I've had a lot of problems with overheating Z240s and I'm hoping to move on from that.