Just done a test on a NetMetal 5 (921UAGS-5SHPacD) with 28 clients associated that runs on v.6.42.1 and latest firmware. AP radio is on 'only-N', 20/40MHz Ce, NV2 protocol, some fixed MCS rates, Hw. Retries = 3, 75% dynamic downlink mode and tdma 2ms period size. I have one client with SEXTANT (v6....