Indeed this information is not well distributed. I tried to get this info too. What I got as an answer is that aethercast is too slow to use with desktop. Not really a helpful information.
From my personal experience I can tell that Meizu MX4, Nexus 5 and BQ10HD tablet do not connect to any of my widi capable TV or MS HDMI stick. (any modern android does)
Rumors say that Meizu 5 Pro already did when canonical was maintaining. Other rumors say that Mariogrip is watching cat videos on his oneplus one with widi. I am sorry I can not say if these devices really do what rumors say.
Maybe this can help you already though.