That depends on your definition of "bad". I have one of the early production .454 Casulls. It began to unlatch due to recoil, to the point where it was dumping four loaded rounds on the ground. I sent it back to Taurus for repair (on my dime, or more accurately $55 for shipping) and it was gone for 3 months. It seems to be fine now, but I'm watching for any signs that it may revert to it's bad habits.
It is an extremely accurate gun, but the the two point cylinder lockup on them is designed all wrong. Had they used a rear lock similar to the Colt double actions, it might work. Any system that requires pushing forwards on one latch and downwards on another is going to unlatch during the recoil of a .454 Casull.