I picked up a MINIX Neo C, all the colors are for sale on Amazon.
No problems with it at all, and flash keys and SD cards mount immediately. Someone had mentioned somewhere that it didn't plug in snugly into the USB-C port, they must have been using a pre-release as it works fine for me.
Haven't tested the HDMI on a 4K monitor, seems to work great on my crappy Asus 17" monitor though.
Ethernet works, but you have to install a third-party driver. Don't use the one in the Minix forums, get the latest one approved for El Capitan direct from the Ethernet chip vendor here:
http://www.asix.com.tw/download.php?sub=driverdetail&PItemID=131
The one in the Minix forums only supports up to Yosemite.
Only two concerns: it is somewhat heavy, and it does get hot, but never uncomfortable to the touch. Being a cheapass, I use it with Apple's 29W adapter and an Anker USB-C to USB-C cable, they certify it as a charge cable, and that Google engineer guy approved of the Anker cable. That cable seems thin to me but as long as it works..
$29 for a damn cable, Apple? Really? The Anker only cost me $10.