The main advantage is that earnings in the fund are taxed at only 15% regardless of how much an individual is otherwise earning.
Secondly, there is no tax on income or lump sums drawn down from the fund by those aged 60 and over.
Thirdly, there are various strategies to ensure that money can be accumulated in the fund, at the same time as drawing down a pension.
Fourthly, SMSF linked to an SMSF Will can be used for estate planning purposes to pass on money to one's children and grandchildren after death. However the Trustee has virtually complete control over the Fund, and this can cause conflict among the surviving beneficiaries.
The main disadvantage with an SMSF is that it normally costs about $1500 in Accounting / Audit fees annually to ensure the Super Fund meets its compliance.
Secondly, the setup fees can be costly. There has to be a legal SMSF Deed, and maybe a SMSF Will, and a dedicated SMSF Corporate Trustee established, to gain maximum benefit from the SMSF.
Thirdly, the Trustee has various obligations which are onerous and unavoidable.
It is not surprising that those who have less than $100,000 in investments tend to choose an Industry (or Retail) Super Fund for their investments.