I would take the white Milgauss and yes, I am biased :)
I like the idea of the defy, but I found the open dial version too symmetrical / industrial, lacks artistic design. I don't know how to pin point it, but it looks they are doing a open dial just for the sake of doing it. The simple blue dial looks lot nicer for me.
Ok, the Milgauss is not going to win any beauty contest neither, but I just love it because its so not-a-Rolex. That orange thunder bolt hand is a love it or hate it thing. You be the judge of that. And consider the white Milgauss having no lume, cause the lume just doesn't work well. Otherwise, in the sea of _________ (filled in your fav popular Rolex models), Milgauss remains to be the few Rolexes that I found more interesting.