I interviewed author Ritchie Vink on my newsletter (NotANumber) some months back, he's smart and the library has a nice design.
I still barely know anyone trying it, it did get a write up just recently here: https://news.ycombinator.com/item?id=32998040
On one of my recent Higher Performance training courses a hedge fund person said they'd tried it with mixed success - some things faster than Pandas, others more expensive on RAM.
I'm hoping to have a play soon but have only lightly tinkered so far.
The parallel-by-design nature is nice, but I think the API is still evolving rapidly making it harder to develop with.