I've used the WD19. I haven't experimented with Linux, but it's a pretty screwy device. A firmware update meant that it stopped playing "which device is going to work today" lucky dip, but it is always a festival of that Windows "hey, something interesting happened at a hardware level" noise as it takes 10 seconds and 3-4 redraws of the whole screen to finally figure out where all the displays are.

It's workable on PC and Mac, but I don't love it.