Contract Pros

1. In most cases, more money
2. You might be able to claim more tax return if you have more expenses because of having your own company
3. More opportunities to learn new stuff and horizontal career growth (arguably)
4. Less involvement in the organisation's politics

Contract Cons

1. Less power to refuse to do any work during your contract unless you are willing to terminate the contract
2. You need to make sure you have enough cash in the bank (enough for at least 6 months)
3. While being between contracts, do not stress out. You need to be cool and calm. You can consider it a holiday and enjoy yourself
4. In some cases, e.g. if your bank savings finished before a new contract started, you should be willing to accept any casual job, e.g. a security guard, a cleaner 

Permanent Pros

1. You don't need to panic every time your contract ends, and nobody is willing to take the decision to renew it 
2. You have more freedom to schedule your holidays
3. More opportunities for free training
4. In most case, more opportunities for promotion (vertical career path)

Permanent Cons

1. In many cases, you need to make sure your objectives are met and your annual evaluation is good 
2. It might be boring after a few years unless you jump on new internal opportunities