there is a debate going on some times back that is it good to write Ramadan or Ramazan. which one is correct.
First of all both are good enough as both directly means to a same occasion or event. For Ramazan, the people of subcontinent or who speak urdu can pronounce a urdu alphabet which sounds like (Zoad) thats make a better pronunciation with Ramazan.

For Ramadan, some how it doesnt make the pronunciation as correctly as Ramazan does,

in the end all these clarification as mine, and can also be debated.