Now I will try to summarize my experience with each system case.
The new series of HEC’s system cases seems to be just as successful as the former series. The 6XR8 is a very good product for its money. It features a nice and demure exterior design, a reliable chassis, good ergonomics and cooling, and a low level of noise. I guess the only drawbacks worth mentioning about it are the inconveniences you may encounter when connecting and laying out the cables of hard drives. Moreover, the default 450W power supply offers a rather limited selection of connectors. The 6XR8-PE comes with a more interesting 600W PSU, but its price goes beyond the mainstream class.
Gigabyte’s GZ-X series represents a reasonable compromise between price and consumer characteristics. Yes, these system cases do not stand out in their class, but they come at an affordable price and have no serious drawbacks. If you just want a regular system case, you should be quite satisfied with one of them.
The Raidmax Smilodon differs greatly from the others. It is eye-catching with its original interior design, multiple fans and aggressive exterior. But when you go into details, you can find that the better cooling comes at a higher level of noise whereas the unusual design is not as handy as it seems (even though there are a few obvious advantages about it). Its default PSU is not exactly high quality, either. Thus, the Smilodon is a system case for PC enthusiasts who need a gaudy computer with good cooling.