I havea Nanopi R5S which failed today.. The device ran Zeek to monitor a span port, so, two ethernet interfaces are sufficient. This is on my home network so the box was never particularly taxed. I am tempted to get the newer R6S. it looks like the R6S will not boot from the NVME (same as the R5S). Not a deal breaker but an annoyance.. I would welcome suggestions for an inexpensive replacement.