I cannot speak for USB with N wifi but do run an ath9k PCI card as a Hostap server with N speeds, although not 5 GHz. It runs fine as WPA2 CCMP. It is getting more features as it matures.(I have run this setup for 2 years now)
I also have an Intel 4965AGN mini PCI card in a netbook that only works to 150 Mbps(be careful of this some cards only do 150 not 300), it has worked well on 5 GHz at Google cannot remember the exact speed, sorry. On a Ralink RT2860 I have seen 90 Mbps iperf through concrete to the ath9k 2.4 GHz Access Point I mentioned above on Ralinks own proprietary drivers. Last time I tried with the rt2x00 or Testing drivers I had issues. A good starting point might be : http://wireless.kernel.org/en/users/Drivers good luck Brett -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
