I just called Garmin because I had a similar question. I want to share data (waypoints) between my old 93 Plus unit and a newly purchased 93 UHD unit. I (we) need the marine networking cable, part # 010-10551-00 to connect the two units. However, as previously stated, this will use the Panoptics port. The tech said to get that box you mentioned or go a cheaper route and use a switch from Netgear...however, it won't be as waterproof as the $250 box. If I ever get Livescope, I'll probably just unplug/unplug cable since I'll be using the Livescope xducer vs TM-mounted xducer.