I got it a few months back.
I have no complaints with it. It has a mic, which you place in the "sweet spot".... where you will be setting during the monitoring and mixing stages. You move the mic around one position at a time in that area. 3 to 4 foot circle...follow the directions..... It plays a test tone sound. The mic picks this up and tries to determine the acoustical abnormalities in the listening area and then saves that as a setting. It is recommended that somewhere between 12 to 24 samples are taken of the sweet spot area to get a good representation of the room.
Upon tracking and mixing, you insert ARC into the master buss and turn it on using the preset. You can have a number of presets for different listening adventures. Smaller , larger, different location sweet spots.... etc...
During playback, ARC will "correct" the sound that is sent to the speakers for you to hear..... essentially, in theory, flattening the sound to avoid the resonant peaks and nulls that have thrown your monitoring situation off in the past. It's supposed to let you hear the true sound of the music taking the room as far out of the picture as possible.
When you are finished..... you turn ARC off and export and listen, and the mix should be better balanced from a sonic point of view to play and sound good across many player platforms.
hope this helps.