What is the difference between 512kb and 1024kb LS1 PCM's?

And which one would you rather have and why?

I'm guessing the 1024kb PCM is for later models and has additional features.

All I know is that it takes around 2 minutes to read a 512kb PCM and 4 minutes to read a 1024kb PCM.
So at this stage the 512kb PCM = WIN.

I'm asking because I'm going to swap my PCM for another hopefully this week and want to know which PCM would suit me better.

1MB PCM is slightly faster and the OS has a few more tables.
On the other side, the 512KB PCM has better custom OS support and all of them have IAC drivers.

Since they are not directly interchangeable unless you rewire the harness, I see no need to go from one to the other.

Okay thank you. Looks like I'm sticking with the same type of PCM..

I forgot to mention that you only need to read the PCM once, for actual tuning you use -Write Cal Only- which takes roughly the same for both, so no real advantage with either.

not sure about things like egr, smog, etc, but for the most part the ecms do not require repinning when swapping between these ecms I do it often. When it comes to swapped vehicles I typically use the early harness but will use the early or late pcm depending on what I am trying to accomplish. I have yet to have to repin anything. OF course I am in the habit of pulling diagrams for both and verifying everything is in order

Thanks guys.