I'm revisting this question because in looking at ON's description of there egg product, there is no mention made of it being an extract of egg whites. In fact, all they say is that they separate the whites from the yolks (nothing magical about that) and pasteurize and "spray dry" them.
Pasteurized eggs are still considered raw eggs, even though they may be free from salmonella. Raw egg whites do not absorb well at all and they will also leach biotin from your body.
If I were to buy any I think I would go with the Protein Factory product, where 0311 took the info from, since they actually make claims about the bioavailibility and mention that the protein is extracted from the whites. I'm not sure this applies to all egg protein products.
But again, I don't really know and am just using the info I have. If anyone knows something I am missing, then please let me know.