Most:
The price-performance ratio.
PMW.
Silence medium power level.
Well finished, makes the sober black and it fits well in most of the boxes.
Cons:
Much less of the product is its attachment system that makes it very hard set on a waterblock for example. The Silent Wings will be more suitable in this case although the price increases significantly for the push / pull for example.
I highly recommend for a quiet and well ventilated config.