This looks nice, but does it even count as SFF at that size?
I think it's mainly just deep. If you look at the photo of the rear, the height doesn't seem much greater than the mini-ITX motherboard. The width isn't much more than than a full-height PCIe card plugged into the motherboard. So, I think it's not much bigger than most mini-ITX chassis of that layout, with the exception of depth.
I have a similar chassis layout that's not as deep, and it was one of the smaller mini-ITX cases available at the time. At least, among those capable of fitting an ATX PSU and a decent 2.5-slot GPU.