the two negatives of adding the 23 BCM are that you now have the beeping of the horn when getting out with the vehicle running(I figured out that the beeping only happens when you close the drivers door so leave it open and it won’t beep). 2nd negative is getting the rear seat warning in the cluster. I think the purpose of it is to keep you from forgetting that you have a kid back there.
One positive I have seen that
@OnTheReel has documented in this thread is that if you have the surround camera system you can get it to automatically turn on the front camera when you are pulling up to an obstruction.