I'm using a killer 1525, but with only oem atheros drivers and no killer software. The killer software was garbage with all those features that would end up causing more trouble than good. The performance is decent, I can't complain. I get ~40MB/s transfer speed with my NAS (on 1Gbps ethernet it tops at 80-90 MB/s). So I am only getting ~320Mbps on 866Mbps connection. That seems to make sense to me, as I hear you only get about 1/3 actual performance. Router is asus ac-68u. My question is if I upgrade to a 9260, will I see any significant performance improvements? Are there any 3x3 mini pci cards out there? Thanks for the help.