Unlike what B&H would like you to believe, the Sony Xperia X hasn't retailed for $399 in a long time. Actually, it's been hovering around the $300 mark since the end of 2016 and has recently dipped to and stayed at $250 on Amazon. However, if B&H wants to call this a DealZone deal, then we shall call it a DealZone deal, even if it's only $20 less than other stores.
Still, you shouldn't scoff at what you get with the Xperia X. You're looking at the North American unlocked variant, which is compatible with AT&T and T-Mobile (band 12 and all). It has midrange specs with a 5" 1080p LCD display, Snapdragon 650, 32GB of storage, 3GB of RAM, but a rather impressive camera setup with a 23MP shooter on the back and 13MP on the front. Keep in mind though that quality seems subjective, with some users praising the resulting images and others saying they expected more from the lens.
The one non-controversial thing about the Xperia X is that Sony takes its software updates seriously and the device has already received Android 7.1.1, more than I can say about many flagship and midrange phones from this year. If that seems like a good deal for you, the link to purchase one is below.