Just DIYed the WP on my car, what was expected to be a two hour job became a four day turnaround.
I got the WP on my VW dealer, "DD" version with the metal impeller, as soon as I started the car after the install of the new pump it started to leak so bad that I lost all the coolant in a matter of seconds. Luckily when I removed it and brought to the dealer they warrantied it and gave me a brand new one which was ordered from Germany and took 2 days to arrive. With the new pump everything went smoothly and now the car is running leak-free, hope this one lasts more than 33k miles.
Changing the pump following some DIYs in this forum is quite easy, and you can ensure everything is clean before installing the new one, so I recommend everyone to do this by themselves.