I recently bought the Nano Modules Serra module and overall, I'm quite pleased with it. On the plus side, it's a very user-friendly module that's easy to use and has a lot of I/O options, making it a versatile addition to any modular setup. It's also well-built and feels sturdy, which is always a good thing.
However, there are a couple of cons to be aware of. First, while the Serra does have an end-of-cycle (EOC) output, it can't be turned into an LFO and doesn't cycle on its own, which limits its usefulness in some contexts. Additionally, the long release time in fast speed mode seems to work best only in the last 80-100% of the knob's range, which may be what I personally use the most.
The attenuator and offset knobs are very useful in practice. And the module is very nicely priced.
I think the Serra is a solid choice for those looking for a simple yet powerful module that offers a lot of I/O options.