Can it be a reliable DD? Yes, definitely, but at over 100K miles it depends entirely on what maintenance has already been performed,
I don't understand the praise.. I owned one for 6 years and I got plenty of ridiculous issue, that could NOT prevented by maintenance. My previous M54 was more robust and had way more character.This example seems clean and well maintained and from what I read the N52 is one of the best engines BMW ever made.
The T-shape valve cover is a bad design and in plastic. The first one was replaced under warranty. I had to pay almost a grand for the second. Other leaks too, oil everywhere
Electrical cooling pump and electronic thermostat are expensive to repair. Another 1.5K, including an expensive hose.
Just before end of warranty, they opened and repair the head as it was severely clattering on cold. When I got rid of it, it was developing again.
Also other nonsenses. There was a noise coming from the differential. Dealer wanted me to split repair (good will) and eat 50% of the $3600 estimated repair.