Conflicting aspects of gunman Man Haron Monis' personality have been revealed in an extraordinary day of testimony at the Sydney siege inquest.

Lawyers who have represented Monis in his many clashes with the law testified at the inquest in Sydney on Friday, with Dr Nazir Daawar describing him as 'a very evil smart guy'.

Dr Daawar says he would have urged police to shoot Monis in the head, 'no negotiation', if he had realised who it was holding 18 people at gunpoint during the siege.

There was some disagreement about Monis's intelligence.

High-profile lawyer Chris Murphy told the court he thought Monis was 'not very intelligent' when he represented him for a day in 2009 but criminal lawyer Manny Conditsis said Monis was articulate and 'a very intelligent man'.

All lawyers spoke of Monis's attention-seeking behaviour and their anger at his performances outside court for the cameras.

The hearing resumes on Monday.

AAP