Okay, Puremusic, I have done some comparisons that might interest you.
I used a cd by Nnenna Freelon called Live. She has a great voice and the backup is very driving. Also being live there is a clear sense of space. I had already made a RealityCheck cd-r using ClearDisc and ClearBit, the original fluids. I listened to the original which had been cleaned with these same fluids. I then Nespaed the original and listened to it. Then the RC cd-r, and finally that cd-r Nespaed.
The original is quite clean and pleasant. I arbitrarily will assign it a 1. I treated the original at the 60 setting, where 30, 60, and 120 are the choices. It was strikingly better, with more detail, sense of space, and improved dynamic. I would assign it a 1.5. I struggled with these numbers and do not really mean to imply that it was 50% better.
Next I listened to the old RC copy. Sometime I will make a Cool Copy cd-r as I have one now. Thus far I prefer the RealityCheck copies slightly.
The RealityCheck copy would get a 2 on my scale. It was strikingly more detailed than the Nespaed original and had greatly more detail and sparkle. It all so had the drive that I have always found with the RC process, if you stick with the original fluids. The bass was far superior than just Nespaing the original, and this disc has driving bass. There was a greater sense of soundstage depth.
Then the ultimate. I double treated the RC cd-r on the Nespa. The first was a run at 60 and then another at 120. My jaw dropped on hearing this. I was there. Her voice was so distinct and real. The soundstage was quite realistic with incredible detail and realism. I could hear those sitting near where she was singing. I would rate this as a 5, clearly greater than its parts.
My understanding of how the Nespa works would suggest it could be of no benefit to cd-rs as they have no metal layer, but it clearly works better on cd-rs. This is troublesome to me as I have been impressed with what the Nespa does for sacds, which of course, cannot be copied.
Tonight I will make another copy using the RealityCheck of the now Nespaed original. I will probably listen to it first and then Nespa the new copy. Again I am inclined to expect no improvement, but given my prior experience, I will not be at all surprised if further Nespaing adds further.
I know better than to generalize from a single disc, but that is the best I can do for now.