The issue is not whether or not they work. The issue is the period of duration for safe use.
Corsodyl has been produced to deal with specific dental problems. I have used it for minor gum irritation. I may have been lucky, or have healthy gums. However, I have found that, when using Corsodyl, my problems have cleared up within a few days- sometimes within a day. I have never had to use it for anything like the maximum extended period.
I cannot agree that Corsodyl is a standard mouthwash. No dentist I am aware of recommends it as a daily mouthwash. My own dentist, (excellent) prescribes it, exclusively, when the problems for which it is manufactured arise.