Synthetic oil?

["Lane Flynn" <vortexic@xxxxxxxxxxxxxxxx>]

It's been nearly 3k miles since I bought my car, so it's about time for the
first oil change (Inspection I had been done right before I bought it).
Most of what I've heard recommends Mobil 1 15w-50.  However, the car has 72k
miles on it, all the previous services were at the dealer at the dealer
intervals (so it's always had dino oil-right?), and I've heard that dino oil
is absorbed by the gaskets differently from synthetic and if I go to
synthetic after so many miles of dino I could get some leaking.  Is this
true?  If so, what kind of dino oil should I put in, and if not, am I right
about M1 15w50?  (I live in Atlanta, so it never gets too cold, but it can
get pretty hot.)
One more question:  John Firestone emailed me directions for installing Park
Ventilation Control (Euro option never available in US 3ers) in a US E36.
Has anyone else done this?  If so, how difficult/potentially problematic is
it (i.e. could I seriously screw anything up)?  Also, how effective is it in
keeping the car cold?  The dealer was a little worried (plus, two of the
parts are euro parts that would have to be shipped from germany and couldn't
be returned no matter what).  As always, TIA.
- --Lane Flynn
94 325is, tired oil, hot interior

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