BC v PA
I have a slightly different answer.
If you are becoming "known" in the casino, play the 4 deck game if it has about the same pen as the six deck. If the 4 deck game pen sucks, play the 6 decker.
If you are not yet known in the casino, Backcount the best pen.
In the meantime, take Don up on his offer. Give him the data and he'll tell you which is the best game.
THEN consider your available bankroll. Careful and patient Backcounting may be your best choice.
Good fortune!