I've had a set on my car for well over 6 yrs. now. The stock end links, like most other suspension parts for our cars, are disposable. However, they're cheap too - at least at this point in time.
Also, you cannot make them up yourself UNLESS you have access to a machining facility. WHY- because the end links must be in a vertical orientation (90 degree angle from control arm) after they're connected to the sway bar. This requires a spacer between the rod end and the sway bar. Without the spacer, the end link leans inwards and puts an angular stress on both the rod end and the bushings resulting in premature wear.
There is 1 proviso to this discussion. IF you have any type of aftermarket (bigger) rr sway bar it will eat up and spit out the stockers at an alarming rate due to the extra force channelled through them. Therefore, unless you like changing them regularly get the better spherical rod end types for use with any aftermarket sway bar.