I’ve had the awesome opportunity to own the Erebus V3, the Hades, and the Abyss. The Erebus V3 was a royal pain in terms of having to constantly tune it, but it did sound great. The Hades was simple but there was something really appealing to the oscillator section. Both of those I ended up selling, though.
The Abyss, on the other hand, is such a beautiful character synth with a variety of ways to get weird and beautiful (e.g. delay, reflections, phaser, more), and is maybe my second favourite synth I own. It sounds incredible, and I hope that someday they revisit the idea of the Abyss, because more people should really get the opportunity to play with it. It’s really a gem.