I'm at like 0-1% idle. ive got everything off running a double nat setup cuz I have to with static wan. but like everything off. running 2.4 in wifiG 20mhz chan6, 5hz on n/ac mode 40mhz chan44. ai-protection off, file sharing off, advanced wifi setting everything off except wmm apsd for mobile power saving. and running qos bandwidth limiter with my dhcp range limited and 3 separate devices static out of dhcp individually limited... things working flawlessly. I still find it too good to be true but 1day so far no issues
I did clear nvram before updating though then updated and did a factory reset from gui, then powered down, and then factory reset with the button on the back. and then re-entered all settings. thought id mention that incase it made the difference