My copy is very good. I've seen reviews however that show somewhat weaker corner performance than I'm seeing, so I'm betting that QC is variable.
Overall I do see some purple fringing at f2.8-f4, it's got typically Chinese flare performance (not as bad as the sub-$100 re-housed CCTV lenses like most of the 25mm or 35mm cheapos, but not competitive with Fuji's stuff). Build quality is outstanding, I was shocked how good it is. Infinity focus was dead on. The focusing tab is nice, wish they'd sell them as an accessory (it's stick-on). MFD is decent but not exceptional. No filter ring, but a 77mm one is available as a ~20USD accessory. Minimum aperture is f16, which surprised me, I was expecting f22. Colours are nice, it does particularly well with the Velvia and Classic Chrome sims.
Honestly, I'd recommend it. I'd recommend it at twice the price if every copy out there was as good as mine is, I'm not seeing nearly as bad corners as the reviews show, although being a landscape guy I didn't really look at f2.8 corner performance as I just don't care about corners wide open, at f5.6-f8 the corners are more than acceptable.
