I looked at a website that shows calendars for various ways to split up the week for the kids. Some of them look really confusing. 2-2-3 looks best to me. I'd guess that's the most popular one.
This is one of the things that got me, too. Initially, it was 2-2-3 for us, but that's a pain so we went to weekly. That may change, too. but we will see. What [censored]-so-much is that the ex's don't really care, even if they think and have been told they are great moms/dads. Whatever.
There are moments in this life when you are so confident in the rightness of your actions, that not even for a second do you consider the option that you might be wrong.