It will work great for any Amiga that uses a floppy drive with a standard face plate. The A3000 like the A500/A600/A1200 use the case as a face for the drive and you need a special eject button.
I was also thinking about an idea like the old ICD Shuffleboard but for the 3000 instead to make the DF0 boot floppy available on the external port. Then you can just remove both of the stock drives and put covers on them. Oh well.
Jeff