Congrats on your two new ball pythons! They look nice and bright!
As for cohabbing: Everyone is going to have their own opinion. My opinion is that it is fine-until it *isn't*. I would separate them before it isn't (which could be anywhere from days/weeks/months/years)...dependent upon the size/quality of the enclosure and the disposition (towards stress) of your specimens.
Also, those half-log hides that are open on two sides aren't ideal for ball pythons. A hide with one entrance, a dark interior, and a tight fit that they can squeeze their body against to anchor themselves in place-is what they want.