I have a Frontier WF-803FT but the best I can get is ~280Mbps up ~380Mbps down with two adapters connected through a 6ft coax, no splitters, filters or anything else in between. I used iperf3 and NetIO for the tests. The same setup with GbE/CAT6/CAT5e cable gets me ~900Mbps.
I set both adapters to full (FULL mode did not connect, aka MoCA light is off, until I unchecked "Preferred NC" on one of the WF-803FT).
Is there something wrong with the Frontier version WF-803FT that throttles the speed? Would changing the firmware to WF-803M fix the problem or the hardware for the Frontier version is different? I can telnet to it if somebody can tell me the right commands (couldn't make any sense out of what I saw with "help" command there).