XYZ Computing has a new article out on the SilverStone CFP51 Bay Converter

SilverStone's CFP51 is a bay converter- an aluminum insert that gets three 5.25" bays and converts it into space for four 3.5" hard drives. Unlike other devices it does not have any features which allow quick access to or swapping of the hard drives, but it allows users to add four drives along with sufficient cooling for each in space that they would otherwise not be taking advantage of. The device is specially designed to match SilverStone's aluminum case design but should fit in any standard ATX with three empty bays.

SilverStone CFP51 Bay Converter Review