Yes, I've tried balut. I'm willing to try most foods that are not considered palatable in our culture, as long as they don't pose a significant health risk. I've declined raw blood and pork, but I've tried lutefisk (lye rinsed off, and properly prepared, of course), fried insects, ant eggs, and I actually like raw oysters, sushi, sashimi from known sources. Fermented fish sauce isn't too bad. Brains and eggs and chitlins in a soul food restaurant was wonderful, but I found out later that I had just ingested over 2000 % of the recommended daily allowance for cholesterol.
It was a very brave person (or dying of starvation, or extremely drunk) that first tried to eat lobster or shrimp. Bottom feeders that eat dead and decaying matter and that look so hideous can't be good to eat.
Balut isn't too bad. It helps a lot if you leave it unrecognizable, by not dissecting it as in the photos. I've eaten the whole thing, even drank the amniotic fluid, the yolk, the embryo, and even scraped the inside of the shell that was covered with some kind of membrane and what appeared to be blood vessels. I must've been very brave, or dying of starvation, or extremely inebriated at that time.