Hey Dan,
I saw Erazer before I bought Defaced. They are two very different effects using a common principle but both the methods and the presentations are different. The clean visual change of the card whilst it's sat in the fan is unique to Defaced and to be honest, the reason I went for it in the first place. Defaced deck also has more scope for modifications to its routine.
Hope that helps too! Yeh, let us know how you get on!

DC