While the circle notation for benzene is popular in high school teaching I have never seen a higherlevel organic chemistry textbook that uses it or met a practicing chemist who uses it The Kekule notation seems to be much more popular among chemists It is overwhelmingly used in all the major chemistry journals I know whether published by the ACS the RCS Elsevier or Wiley In my opinion the reason is that once you go beyond benzene and start to look at heterocycles polycyclic aromatic molecules reactive intermediates and reaction mechanisms the Kekule notation makes electron counting and electron pushing much more straightforward The circle notation only seems to be common for some organometallic compounds such as ferrocene and some aromatic ions such as the cyclopentadienyl anion and the tropylium cation