In my experience, everything's interchangeable - I've never had fit issues with different manufacturer's gear, "X" head on "Y" sticks, "W" head on "Z" flat adapter, etc. I even have a cheap asian ball adapter for my crane and it works fine.
It can become a really pain in the behind.
For instance Sachtler heads have relatively short stud so they don't really fit well on Manfrotto legs or Cinevate bowls. You have to get replacement stud (expensive). Still if you go into it knowing that it WILL require some re-engineering and looking for parts - you will be fine.