I'm going to upgrade my late 2015 iMac 5K to the new 2017 iMac 5K. I have an external monitor (NEC MultiSync EA 275 UHD) that is connected to my current 2015 iMac 5k using a Mini DisplayPort (plugged into TB2 port on iMac) to DisplayPort (on NEC monitor) cable. I mirror the two displays so I can move back and forth between a standing and sitting workstation at my desk. The new iMacs have USB3/TB3 ports, but no TB2 ports. So what will be the best way of connecting the new iMac to the NEC? I am thinking about the USB-C Digital AV Multiport device. The description seems to suggest that it will do what I need: However, the reviews are TERRIBLE. Most people say the HDMI blinks in and out and the hardware is faulty. Maybe just this simpler USB-C to DisplayPort cable would work? I'm not really clear on whether I need to use the DisplayPort or HDMI port on the NEC. I seem to recall that when I used HDMI in the past, the NEC didn't properly mirror the iMac. So maybe I actually do need the DisplayPort. Any other ideas/options? Thanks.