Advanced Heuristics in Real Time Scanner

Ok I have noticed that the Advanced Heuristic in the Real-Time System protection is unchecked however I checked in the ThreatSense Parameter Setup.
Can someone explain to me the difference? What does Threatsense do and why does it need advance heuristic in REal Time protection and what difference does it make that the AH are unchecked in the "Advanced Setup" portion of the REal Time System Protection?

I had Nod2.7 and always had AH on in my AMON and IMON. By unchecking the AH in the Advance Setup in RT Protection am I basically unchecking AH in AMON?
How large of an impact does this choice on my security and how much of a resource increase will I see by unchecking it and vice-versa?

 

by default,AH is not enabled in real-time protection except for the newly created and modified files.

That measn ESET NOD32 will not perform AH on each files unless the file is newly created or being modified.

please notices that enable AH for each files (check the option in ThreatSense Parameter Setup)may slow the execution of some programs due to increased system requirements.