Positive casters allow more negative camber for the out side wheel , this will allow the car to have better turn in. The RCA can realign the RC of a lowered car, but since what the market offered are all predetermined in height, therfore more adjust to certain part is required to make it perfect.
The offset pillow ball bushing give about 3 degree more -casters as a FF cars cannot have too much casters like a FR cars. this is sufficient and at a safe level for all street and track use.
Wear on pillow ball are due to installation and poor quality issue. The angle is not that great to sustain heavy wear and tear. All suspension parts with buhsing need special ways to install proper fitment , this is somthing most shops just ignore or are too ignorance about it
There are good quality pilow ball with teflon liner for self lubrication availbale, and been tested in MME DC5, DC2, EK, EG6. at 1/3 the prices of so call well known source. Sometime brand play too great a impression that people are paying too much or just getting low quality stuff.