I hate that for you. Even though they recommend not using external lightening arrestors we do anyway, $35 vs $500 for the B5c's, more for the B11's. It works just fine with the external LPU. We did this with our B11 links too and had port flapping issues for a couple days but that subsided and has not reappeared, it's been 4 months now. We lost one LPU and no radios in the meantime.