madeleine

Yes, it is accurate because the author of Sejarah Melayu is Tun Sri Lanang who used to be the Bendahara to sultan of Johore (the prime minister). Because he works in a royal family, he gains access and has the first-hand knowledge to the information of the royal family. The characters in the Sejarah Melayu are based on real historical figures. 

No, it is not accurate because the stories are based on imagination and fiction. The stories are like Ancecdotes, which is short and entertaining stories, sometimes they are very exaggerating. For example, Bandang who has super strength or Sang Nila Utama who threw the crown into the sea and the storm immediately stopped. It is just a coincidence.

Actually, there is no other evidence that can support that Sang Nila Utama is the same person as Sri Tri Buana because in Sejarah Melayu, it uses this name.