Comparing 4000 and 6000 series

[CompFi]

New to the forum and planning to become a new owner in 2022. Lots of questions for the braintrust here but I am trying to do my homework first.

After scanning the forum, I did not see a recent thread comparing the CSX 4000 and 6000 series. I am most interested in your perspectives on the differences in performance and value, if any.

I am wondering if there are fundamental differences between the series themselves, less focused on the specific differences between any two cars – for example 4999 and 6000.

Question about value. How would you assess value across the two series? Maybe a specific question would be more helpful here: how would you use comps from recent sales of a 4000 car and a 6000 car that have similar specs? At least similar to my untrained eye anyway.

With the passing of Mr. Shelby, what do you think the effect will be on the long term value of the recent 6000 series cars that don’t have his signature on the MSO?

Thanks,
Brian