A couple more differences between EZD and SD2 that haven't been mentioned yet:
Superior samples are larger and take up more RAM (more velocity layers, more round-robin alternates, multiple mic positions, plus bleed and ambiance samples). Consequently, SD2 provides a couple of memory-conservation options: the choice of 16- or 24-bit samples, and the ability to purge unused samples.
Superior eats more CPU, too. The effects are pretty hungry, especially if you use any of the Toontrack presets, which are over the top with effects (I recommend you only use the presets to get ideas). But they're good effects, especially the compressor on overheads and/or room and the transient shaper on kick, snare or toms.