There are also mandatory service provisions on a Millenium Overhaul to
maintain warrantee. I heard that one of them is the owner cannot
perform oil changes (must be done by an A&P), and mandatory oil
analysis.

I have not heard this, and I've changed my own oil.

In 2002 we field overhauled our O-540 with all Millenium parts. This
has turned out to be an excellent decision, as it allowed us to dodge a
couple of Lycoming-specific ADs.

After four years and 600 or so hours, the engine burns little oil, has
nearly perfect compression, and starts like a car. We've been very
happy with it.
--
Jay Honeck
Owner/Innkeeper
www.AlexisParkInn.com
"Your Aviation Destination