Bluebee, I feel your pain when it comes to deciding on parts when there is more than 1 to pick from.. On this specific issue I have a small tidbit. At 120K, I replaced my original wp with a Bosch while dong a cooling system revamp. Two weeks later developed a leak that originated from the wp. Replaced it with the original that I took out and no leak. Now I have to do the job again at 200K, but at 160K the original BMW one is still running strong.
Either you are part of the solution, or you are part of the problem.