I guess I have had 4 of them for repair. One had no wear suggesting it had never run since new. After polishing the pivots, completely cleaning the movement and the springs, it ran like a champ. Two of the other 3 ran decently after full overhauls. The 4th one I could NEVER get it to run with its original pendulum, following all the necessary repairs including new mainsprings. It would run with a pendulum off one of the other clocks, so there was something in the balance or rotation of its pendulum that was not right. I spent a lot of time trying to figure out a solution. Its owner took it back finally recognizing it looked nice on the shelf and he would make it someone else problem. Oh, and a few months ago I had a question from the now owner of one of them as to why it was not striking correctly. Since I repaired it 30 years ago warranty may have expired. So, I had a 75% success rate originally, to your question. Here is one of them at auction recently. By the way, the pendulums on these tend to be quite fragile in many cases, so be aware if you handle one of them.
I've owned a couple of these and worked on a half-dozen others, from the 30-Day to Year-Going variety. All but two ran with normal service and being sure the pendulums were properly poised. The two that didn't were badly worn as received and some parts missing, required a good bit of reconstruction but eventually got them to run OK.
I've moved this thread to the 400-Day, Atmos, and Other Torsion Clocks Forum for more exposure.