hebele There is something psychological about it.
Not surprising! I think it makes the piano look like it's been neglected. I completely ignored that when I was evaluating my piano before buying it, but by that point, I had been piano shopping for months and had learned a lot about how to evaluate used pianos. So I had a laser focus on the sound/action/touch etc.
But I was very, very happy with how pretty it cleaned up after I tried the Flitz! ๐