When SteelSeries first talked about the Apex Pro to the media, and indeed the entire Apex series of keyboards, they did so via a cryptic message with the tagline "Experience the next big innovation from the makers of the original mechanical gaming keyboard".
Good implementation of the Hall effect for actuation point control; Integrated OLED display for real-time notifications and customization; Very powerful software driver with a lot of third-party app support; Full programmability allows for the use of different OS/typing/language layouts; Per-key...
Very expensive relative to the average mechanical keyboard; Software driver needs to be more unified in all the features it offers; OmniPoint switches are only in the alphanumeric section; Stock keycaps are mediocre at best and will wear out sooner rather than later