No hands on experience, but I always admired the "look", if not the function.

Frank de Haas and others pretty much condemned these as not worth the time/trouble; especially the 22 Hornet version. He was less critical of the rimfire version, but it too was not without issues.
If I ever found a RF version at the right price, I might be tempted to take a chance on one (but then, I can be a slow learner when it comes to elegant single shots)