The balljoints on my car were, I believe, factory original to a fox-body, and were "lubed for life". I installed them 3 years ago as part of a used assembly with A-arms containing Delrin bushings and SN95 spindles and hubs. At the same time I installed Global West 800-lb front springs and Koni DA's. I was never quite happy with the ride height, it seemd a tad too high for me.
The other day I noticed the car's steering failing to return to center on occasion. As I'd recently installed a MM bumpsteer kit and had MM c/c plates I figured it was time for new balljoints. So I ordered up a set of Steeda X2's knowing that by installing them I could either lower the fron 1/2 an inch with no roll center penalty, or keep the same height and improve the roll center if I installed the included spacers.
I decided to install them without the spacers and take the drop.
Other than the fact that I learned immediately after installing them that I could have saved a boatload of money on them (see this thread https://www.corral.net/forums/showthread.php?t=704278
), I am totally pleased with the results.
The improvement in ride quality is simply amazing. Ride harshness I had always blamed on the Koni's was clearly friction in the balljoints the entire time. It soaks up even small impacts much better than before.
Handling-wise, I can't quantify it yet, but the front end digs in so much harder that I now have to be on the watch for oversteer more than ever before.
The car is much more enjoyable to drive, and I fully expect I'll pick up some time on autocross and road course that I'd previously been leaving on the table.