Initially launched in the US for $699, the XZs was subject to a $79 price cut a couple of months ago - however, that was the case only for the black version of the handset. Right now, both Amazon and Best Buy are selling the unlocked Xperia XZs for $599.99, regardless of color variant (black, blue, or silver).
It's not clear if this a permanent price cut, so you'd better act fast if you want to get the Xperia XZs for $599. In case you're wondering, this is the official US variant of the phone (warranty included), and is fully compatible only with GSM/LTE networks like AT&, T-Mobile, Cricket Wireless, MetroPCS, and so on.
Currently running Android 7 Nougat, the Sony Xperia XZs will definitely be updated to Android O - let's hope it will happen shortly after Google releases this new version of Android. Meanwhile, for more details about the smartphone, feel free to check out our Xperia XZs review.