I replaced mine in about 15 minutes, going slowly and being careful not to mar the outer leather part of the handle.

I didn't know whether the chinese knockoff parts (about $20 on ebay) would be satisfactory, so I bought an OEM one for about $50.

Very happy with the results.

Funny story: I was surprised Monday when my Uber turned out to be an X5 E70. Sure enough, the door handle was sticky. The driver was grateful to learn how easy and cheap it is to fix it.