What is the difference between the 3 128K ROM sets ?

Pina writes that there were three versions.

You can determine the version by pushing the interrupt button and typing "DM400000" without the quotes at the ">" prompt

Top row - top of the second and third columns - the version numbers work out as follows:

4D1E EExx = version 1

4D1E EAxx = version 2

4D1F 81xx = version 3

So what's the difference between these 3?

Does anyone know the difference? The reason I ask - I have version 2 ROMS in my Mac and I have a set of version 3 ROMS handy - I'm wondering what the difference will be if I put them in a 512K Mac....

Lumpy