Hello All .. I stumbled onto this website a few weeks back and I've been addicted to it ever since. There is a TON of good information for a Newbie like me. Anyhow I just bought a '03 WRX and Im wondering is it a MUST to use the Premium (91 Octane) Gasoline in it?? The previous owner used premium so Im wondering if its a MUST to stay with the same gas. Thanks in advance..