I wish it were good 99% of the time. I am finding that it helps, in my case, maybe 30% at best. Which leaves me with my original contention. I am fortunate to have found the socket head variations from McMasters-Carr which are essentially as good on a "scale" basis, and much more reliable.
One possible factor with my button head problems is the needing to use a thread blocker (this is a WW-I vibration machine). Even though my fasteners are all stainless, and the little clevises are brass, they tend to get rather stuck over time with the thread blocker.