Which area do you go? Technical or non-tech?

Contract technical will be paid higher than permanent and non-tech is otherway around.

The benefit and bonus will depends on the paymaster

And you dont have personal KPI or all HR performance BS to to present to your boss

No. Just get consent (may require an interview session) from your future superior then he/she will proceed with the next step.

Note that in order for him to create your position, he need to justify with the management on why he need someone to do the job immediately.

After the position is approved, and you passed the interview with him, he will contact the external HR company to hire you. You will get the offer letter from that company with the company's letterhead (not petronas). You will be regarded as working for that company (not petronas) and all your income and claims will be processed by that company.

But then your identity will stay as a petronas staff but you are not much bound with the requirement by petronas.

1. SI is only for permanent staff hiring
2. Yes, as mentioned before, u may get into permanent status with superior recommendation, but with less pay since the benefit is higher cf. contract with higher pay and less benefits.
3. it really depends on urself once the offer status is given; some ppl x want to have strings attached, so they ought for contract - easier to jump2 around, but for those who are into job security, might as well choose the perm offer.