Maybe because my car is an 06 and fairly early in the S197 series, it has always suffered from the clunk. Go over some not too rough railroad tracks and something felt loose in the front end and a clunking. I read a bunch of posts and some were sway bar end links, some were control arms, and some were strut mounts. I saw where Ford had an upgraded end link and thought it was worth a shot. The new links also use some really heavy duty nuts too. So I bought the links and nuts, but then saw a deal on a Eibach sway bar kit (35101.320 part number) and thought, why not it's only money.
I guess the mechanical gods were smiling on me, no more clunk and the whole car feels noticeably tighter. I happen to be one of those guys that adapt to whatever equipment he has and a change has to be pretty significant for me to notice. A lot of aftermarket parts don't do much and are just a wast of money. This one was a winner.
I've included a pic of the new style link (aluminum) and the old style too.