UnicornPegasus & Griffon's lists are pretty accurate. Like Augen, my brother and I got burned as well. Thankfully it wasn't a costly mistake. We've learned a lot from the "Kotobukiya Bishoujo Collectors" group on Facebook.
Turning the experience into a positive, I've posted comparison pics of my recast and authentic pieces. Since Koto posts photos of the prototypes on the website and not production pieces, it can be tough/confusing to see the difference. Hopefully these comparison shots can help someone else learn from my mistake.
Fake vs. Authentic
Note the bootleg's rougher PVC cast and paint blending on the hair. Bootleg's dress has blue shading and white frills while authentic's dress has white hues and clear frills.
Note bootleg's upper thigh with rough vertical seam.
Bootleg's stockings have a huge seam and tighter mesh.