I also have all these, Aeon Rhythmic, Signal/Substance, and Orbit/Eclipse. All of them are great quality sounds in my opinion.
Aeon - punchy and aggressive. The sound design is what makes this library really special - their loops are more varied and rich. I feel like they used a lot more sequencing on the parameters of more creative sound design tools, going way beyond some of the more standard pulse creation techniques. Many of the loops inspire me to make entire songs built around one of their loop as a starting point. The workflow for tweaking their loops lies primarily around sequencing the FX and splicing. It's kind of a "tweak for creative purposes" approach to creating new loops from the existing material. But I sheepishly admit, so far I've been so happy with using Aeon loops as-is, I hadn't even felt the need to explore their tweaking features, I just have used their 5 main menus so far.
Signal/Substance - the pulses are more traditional arp-like, but IMO high quality and very useful. These libraries are especially great when you already know the kind of sound you want, and you just want to quickly find it - because the sounds are all organized by tags with a search interface directly in the Kontakt UI. The tweaking workflow is different than Heavyocity's approach. It's more about "tweak the FX to adjust the tone" approach. Signal and Substance may have different workflow features, can't remember right now.
Orbit/Eclipse - the selling point of these libraries is their unique perspective of how pulses are constructed. This makes it easy to dig slightly deeper into designing your own pulses. This is also a "tweak for creative purposes" approach, but more of a simplified tool to do some basic hands-on pulse creation. So in that way it's more flexible. On the other hand, having only 4 elements to tweak can possibly be constricting if you wanted to design more complicated pulses. But while using it, I never really felt so unhappy about this constraint. still a pleasure to use.
Also worth mentioning two other useful ways to make pulses beyond just sample libraries:
- sequencing FX like Tantra. This is another way to create pulses from any other source material, whether it's pulse-like or not. This allows to create more evolving sounds (if the underlying sound also evolves), or to have more control over the pulse creation process when you know more specifically the kind of FX you want, and want control over the exact sequencing envelopes.
- using a vocoder to combine percussive and timbral sounds. I haven't done this much myself, because I don't have any vocoder plugin (is there a stock vocoder in Cubase? I'm not aware of it)