She did a follow-up on this on a recent Q&A with Adam Savage. She doesn't use it at all, because her stump is too small. This means she has almost no leverage and strength in the stump. She said she likes the aesthetics but it's not practical.
Imho she needs something with like a servo assist or something hydraulic. But that means stuff like a power supply, pump, sensor, controller, plumbing etc. It would get messy fast for something that's on your hand. If it's more of the hand it could make sense, but the loss of only the little finger probably has almost zero impact on the use of the hand.