I just tried this out too, and it does help in my situation.  I have a speaker in the corner which creates way too much bass, but with ARC on, the difference in the two speakers is a bit too drastic.  With this setting on, ARC has a slightly less profound effect on the sound, but overall it is much more balanced and natural.  It is a nice option for me. I need to get used to it by listening to a bunch of stuff, but I'll be keeping it on for sure.

mikedocy
Just food for thought:
 
There was a recent thread where the op noticed ARC was causing mono material to sound stereo-ized in headphones because of the phase differences between L and R.
 
Although ARC was not made for headphones, perhaps the "Combined L/R Correction" would solve this "problem" too, and/or verify that phasing was the cause? 

I think that the phasing in question is intentional and integral to the correction. When heard on speakers in the room it's correcting for, it doesn't sound like phasing because it's moved the audio "in phase," but through headphones where that phase correction is not needed, the audio sounds out of phase. 

yes, this is 'monitor/room' correction, not headphone correction.
 
sonarworks has that.