Which version of Gigapixel is best for illustration? What would it's best settings be?

I have a batch of animal illustrations that need enlarging which some shading in them. I have a separate computer that I could use for this which would be useful for me.

Would I be better just mixing these with my other images and just putting the latest version on auto, or is there an older version which is better for this?

You probably want to indicate which Topaz app you are referring to as there are at least four.