Originally Posted by Overboost

As I mentioned, both my M54 engines have been running strictly regular fuel for 13 years now. My guess is if a valve would burn because of my choice of fuel, it would have burnt by now. About 150,000 miles on the X5 and 175,000 miles on the E46 running regular fuel.

Not going to say it is the best fuel to run, but paranoia about burnt valves running regular unleaded has been debunked to say the least.