I ran the ARC software when I first unboxed my Anthem MRX 520 receiver, Paradigm Prestige 75F's, and Paradigm center, surround, and subwoofer (from their Classic Collection). I put 250 hours on the system and decided to re-run the ARC software to see if there were differences. There were new values, most significantly for the subwoofer, so I uploaded the data, and I'm glad I did. When playing back 2 channel material (the 75F's and the subwoofer being active) the overall presentation of the bass in the music is vastly improved. This improvement in the low end presentation is also evident when listening to movies in 5.1 mode. In my opinion, re-running the ARC software after giving the system time to break in is a must. The level of improvement in the sound of the system really blew me away.