Again, it doesn't really matter that Miki 3 bends better at the waist.  If you're doing any kind of render where your figure is wearing clothes, that has minimal effect on what you're doing.

 

Elbows and knees however have a huge effect because they're uncovered far more often.  In all of the renders on the other forum, V4's elbows and knees look 1000 times better than Miki 3.0.  Miki 3.0 gets some pretty bad distortion at even relatively light elbow and knee bends on both the inside and outside of the joints.  V4 doesn't and therefore pretty much makes Miki 3.0 not worth buying.