I would read very carefully the break costs on any of these...

I would read very carefully the break costs on any of these fixed rate products.
Most lender will charge you the difference between the fixed rate and the current rate for the fixed period remaining.
If you fix at 6.5% and the standard variable falls to 4% with 5years remaining on the loan you would be up for a minimum of $62,500 in break costs.
Worth thinking about.