One of the external 5.25-inch bays can be transformed into a 3.5-inch one if necessary.
There are no brackets in front of the drive bays. The Cooler Master developers must have thought that the metallic mesh of the front panel offers enough protection.
The quick and easy mechanism for installing 5.25-inch devices is indeed quick and easy (you just insert your drive and push the spring-loaded button to fix it with prongs) but these are in fact all of its advantages.
The fastening is insecure because the thin prongs fix the drive from one side only, so it remains rather loose in its bay. It's impossible to put unused locks on the other side of the bay due to the lack of appropriate holes.
Well, the drive bays allow fastening the devices with screws, and we’d recommend you to use this opportunity.
The HDD rack has a couple of metallic struts in the middle to ensure that each bay is properly fixed inside.
HDDs (of the 3.5-inch format only) are installed by means of plastic guides which have rubber vibration-absorbing pads. The noise and vibration are further reduced through the contact of the metallic HDD rack with the plastic of the guide. The installation process is fast and handy and doesn’t call for a screwdriver.
There are rather large vent holes in the HDD rack. The installed drives are going to be cooled well by the front-panel fan.
As opposed to the above-discussed products, the side panels of this system case are monumentally strong. Although they are only 0.8 millimeters thick (equal to the Element G and inferior to the XPredator in thickness), the extrusions ensure the best rigidity. Besides, the relief surface expands the capacity of the compartment for cables and may even allow to install a CPU cooler which is taller than the officially specified 160 millimeters (this depends on whether the top of the cooler fits into the relief part of the side panel or not). The 0.6mm chassis is as rigid as the “thicker” AeroCool, too.
The HAF 922 is in between the Element G and the XPredator in terms of dimensions, but offers more room for expansion cards than either of its opponents.