The only thing I would have liked to see with the PA-600 was one more full bay, but in reality, that was a minor complaint. Palo Alto was gracious enough to provide the more upscale ATCX mid-tower for review. The similarity in design is apparent however there are enough differences between these two cases to set the ATCX apart. What really makes the ATCX unique is that it can be ordered in a mid-tower or a desktop configuration. This is due to the fact that Palo Alto shipped it to me with the optional panels to convert it into a desktop case.
Some vendors do sell the optional kits to convert from one format to the other.
While looking at the front bezel I noticed that when used as a desktop case that there is one less external half bay. You will still be able to use the bay internally so the overall capacity of the case is not changed. The case access panel is a little more difficult to remove than the cover on the PA600. It utilizes a thumbscrew and two retaining mechanisms that must be pinched inward while sliding the cover back. The unit features the same high quality plastic as the previous case and deburred metal edges within.