2600 version is quite good. The main thing that stands out vs the arcade is that the 2600 does not rotate the character on the left and right sides of the screen. If they are going to do that, he maybe also shouldn't rotate on the bottom as it looks a bit off that way. Other than that, great port, and I have an original Zoo Keeper cabinet.
Pretty rocking game on the 2600. Just hoping the character rotation can be as per the original.