Lots of conjecture from folks who haven't even seen the Swarovski X5 in person, let alone fielded it.
FWIW, There was a YouTube video of a guy throwing his Swarovski Z6 in a pond overnight, then dragging it behind his UTV all over his ranch. He then shot it with a shotgun at fairly close range. It held zero through all of the above. The video isn't up anymore, but discussion about it still exists.
http://www.longrangehunting.com/forums/f18/swarovski-torture-tests-videos-65599/Take it for what it's worth, it was on the Internet, so it must be true.