Have you experienced the "coolant Pipe Leak" and what model and year??

 

Most it's 545 models and 745. It's not many reports for 550, but it has reports for 750. So I guess it's not too bad.

 

I had that go on my 2005 545i at around 120k. Replaced the valley pan gasket and the pipe. I think the repair was like $1500, which probably incorporated a decent discount. Leaking coolant was apparent behind the engine block and on the catalytic converts/exhaust pipes - you could smell the burning coolant from under the car while at idle.

 

I had a coolant leak on my car around 60k miles, I had to replace some of the hoses I believe.

 

I have observed the same. How many miles on your 550i?