Given the memory-compatibility improvements between Zen and Zen+, I'd go with the Zen+ chip. The 2700x also comes with the superior Wrath cooler for what its worth.
Interesting. On that note, I'm going to be rolling the dice with some ECC memory
which isn't on the QVL, and on a motherboard which doesn't fully explain its ECC support (not that any of the others do). With that in mind, the chip with the better memory compatibility is probably a good idea. A quick glance at the Anandtech review shows it using about 30 watts more
than the 1600 under load, which isn't too terrible considering it will be idle much more often than not. 8/16 is actually very overpowered for what I'll be doing (light duty NAS with a little bit of PLEX streaming).