When changing out my PS hoses over the weekend I noticed a small amount of oil seepage around the oil level sensor #9 here
RealOEM.com BMW E39 M5 Oil pan bottom part, oil level indicator). Nothing major but I'm assuming that the gasket is starting to give up.
Do the sensors themselves have any history of failure? I checked a number of posts, but didn't seem to be a clear consensus (unlike the FSU for instance). At $100 +/- for the sensor is it a false economy to reuse it or will I be pulling out again in 12 months? Haven't had any issues with it other than the small leak.