The oil separator is being touted by the supercharger crowd. Anything with a PCV valve is going to get some crud in the intake. But if the engine is sound, it will take many years and many miles to accumulate to the point of any concern, if it ever did. And usually it doesn't.

The point of the oil separator recommendation is to keep the oil out of the intake stream when the engine is under load. Oil has no octane and the supercharged engines are much more prone to detonation so any oil in the intake tract is considered unacceptable by some owners. Obviously, the Mopar engineers didn't think one was necessary, but..............

Today's engines are much 'tighter' than our engines from the 60s and 70s. And our old engines have PCV valves too. So why aren't we concerned about oil in the intake tract on them, too? The separator is a good idea, but certainly not necessary for any car that is not on the ragged edge of detonation and is in good shape internally.

On the original question about which oil to use, when the vehicle is under warranty, it would be prudent to use the factory recommended oil and filter. After the warranty period has expired, there are any number of oils and filters that will serve just as well for a lot less money.