What is the "forum record" for miles on an original BMW engine block, cams and heads?

I have a new-to-me 2000 540i with 96,000 miles on the odo. I'm looking at extended warranties (have one now, till Nov this year), and I'm checking in to engine life expectancy.

In a recent Autoweek, I found Vines Auto, a BMW salvage in Alabama. I called and talked with a guy there for about 30 minutes and learned quite a bit. He said his wife has a 540i with the first generation of Alusil block (4.0 liter), and she has 190,000 miles on the original block, heads, cams, etc., with no signs of impending problems.

He says if no fuel injector or spark problems occur that might cause unburned fuel to wash down the cylinder walls that the Alusil can far outlive steel cylinders. Most all problems he sees with blocks are due to fuel wash problems, and second to that, overheating. He sees very few, if any, camshaft wear problems as long as oil changes have been maintained correctly. He also has reman engines, short blocks and long blocks, as well as reman cyl heads in pairs or singles.