I spent some time working with an early model Twiddler many years ago for a prototype we were building for an industrial application. I loved the idea and was a

I spent some time working with an early model Twiddler many years ago for a prototype we were building for an industrial application. I loved the idea and was able to get to a pretty decent speed with it, but it was really hard on my wrist. I would not recommend it for constant use. I've since developed some tendinitis and occasional trigger finger (all unrelated to Twiddler use), and I can say it would be a terrible idea for me to try to use one now as gripping makes it worse.