Hey guys, Just want an opinion regarding a waterpump replacement part for an E32, or for any Bimmir for that matter. I have a huge headache as I have been going back and forth on this matter with new research coming in. I may be over analyzing but... I prefer to install OE Genuine BMW parts, Yes they are expensive but you pay for what you get..Quality. However in this case, I am not so sure. The genuine BMW waterpump is constructed from a plastic (or composite) impeller. The composite impellers tend to disintegrate overtime, causing the WP to fail and thus lead to overheating. I went to the local BMW dealer and had them reference the part. There have been no changes in part number, therefore, same part as factory installed and is therefore plastic/composite. I dont mind paying for quality, but if it's a design flaw, then shame on BMW for not fixing it with a metal impeller. The OEM parts (graf and geba) seem to have a metal impeller, which logically speaking, would fix the design flaw of the composite impeller disintegrating over time from heat and wear, etc. However, these cost roughly $45 to $55 compared to the genuine bmw's $200 or so. The issue with metal impellers is that they are heavier and may cause premature bearing failure. Even if it is not premature, the bearings in these fail and seize up the motor...........that is catastrophic. Just imagine the implications driving on the highway at high speed. <<<<--------------- dont want to be that guy. The Positive side of a composite or plastic impeller is that once it fails, the pieces disintegrate and the coolant leaks from the weep hole. Also, if you are vigilant you should see the temp gauge go up and you can turn off the engine. Again, at high speed on the highway this is not ideal. However, the impeller will or SHOULD fail before the bearing does. This will prevent the motor from seizing up. Maybe BMW was smarter than we all think and this was the point. I just dont like the idea of buying a cheap part and a cheap bearing is bad news. I would also like to point out that I have no problem doing preventative maintenance and either way I go, I would be comfortable changing the WP every 30k miles. 50K miles? to me $200 for a pump is cheap insurance. Point is, I dont want it to fail if it does and there goes my engine. Thanks guys!