I would not wait. I had a bad spring seat (front strut mount) on my 850. I let it go a few months or so. The bearing plate turned out to be bad on that side, too - lots of play. Possibly the bad seat eventually took the plate with it due to lots of bouncing around (city driver). I did not replace any other parts - saw no reason to - and have not seen any further problems in about a year. For budgetary reasons I would not personally replace a strut unless I saw clear evidence it was bad (though I do check all suspension parts a couple of times a year). I don't know if by end-links you mean the links to the stabilizer (sway bar). In 135K of driving I have replaced each of these twice (using factory parts).