You seem to think that this may be an isolated incident based on your knowledge. I too have your springs, sways, end links, trailing arms on my car as well along with 22's pretty much the same set up as PQ but I have trailing arms and end links.
In your opinion do you think horsepower or driving habits may have anything to do with this? While I do not track my car I may ocassionally get on it just to air it out, lol. Also is this a part that needs to be check periodically like oil changes etc...
Just asking from a knowledge standpoint.
MUSTANG...Like Bringing a Hot Dog to a Steak Dinner....There is no comparison.