I just received this flash and did some testing. Pretty decent unit. The build quality is noticeably inferior to Nikon flashes, but the light is just as good as the SB 900. I can easily mistake the difference in build quality for a huge drop in price. The rest of the flash has worked flawlessly so far. It's too early to say how this will work in the long term. I wish there were more tilt levels in the flash head. It only has two fixed positions, but I put it between the steps and stay there while I'm shooting, so it's not a big deal. That and a bit of awkwardness in the UI are the reasons I downgraded the stars to 4. I mainly use it as a slave and haven't encountered any problems.
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