April 11th 2016 Verified user
I have 2 cases with caddies that require attaching a drive by 4 screws into the bottom. For the life of me I could not get these to work. You need to mount through the sides, also space is a bit tight if your SATA cables have a big clip on them or an L end you'll run into trouble, other than that, if you mount your drives from the sides and have simple straight cables you should be happy enough.
Review of Metal internal 2.5-inch SSD/HDD mounting kit (for up to 2x 2.5-inch drives per 3.5-inch bay)