I replaced upper and lower hoses shortly after I bought the car at around 200k km and at least one of them were Rein and still good many years later at 500k km. That being said the originals didn't look bad either and I actually kept them thinking that if the Rein hose(s) didn't work out I would put them back on!

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1988 325is (purchased new) sold
2004 X5 3.0 2005 X3 2.5
2008 X5 3.0 (new to me)