In a SFF Network exclusive, we take a took at a early SilverStone prototype of a 450W fanless (you read that right, completely passively cooled) SFX-L power supply here at Computex 2017!..
ETA "by the middle of this year" according to SilverStone representative at another forum. I guess this fits nicely with Q2, since any mention of quarter automatically means the very last day that of that quarter. It could then also mean a "paper launch", and we have to wait a couple of months extra for the units to arrive by boat.
But if SilverStone is reading this, we don't mind an update.