Yeah AU-55 details cleaned won't slab problem coins are best sold for non problem coins , even if lower in grade. It will always be a problem coin and tough to sell whenever.
If you took it to pcgs they would probably grade it AU-cleaned. But if you took it to a worse less notable grader, like Anacs, they might not catch the cleaning and give it ms-60.
From the Warman's U.S. Coins & Currency Field Guide. I plan on getting the Redbook as well sometime soon
[FONT=&][FONT=&] [/FONT] The issue is not so much they change, but that they are poor value guides/estimates to begin with, especially for infrequently traded material. To use the redbook as an example, you will often hear people say that it is “outdated” by the time it is released, and while this may be true to some extent, the real issue is where their “values” come from (Google it). The fact is that, generally speaking, most redbook values are inflated, especially for modern coins, while others are more realistic and some are undervalued. There is lots of good info in the book, but generic-yet-realistic market values are not included. Take from the book what you can, but the key here is to know the/your market.[/FONT]