How much safer is 94 octane gas then 91?

[B16a2 Sleeper]

I'm planning on boostin my 00 civic Si with a greddy turbo soon.My question is, Since Sunoco in my area has ultra 94 gas,and I have heard most states get only 91.How much more safer would my car be when boosting. Im plannin on gettin a AEM EMS and only boosting the stock boost with intercooler. Or would there be only minimal advantages having 94 instead of 91.

[Dr Drew]

It is almost always better to use higher octane fuel. How much safer is it ?? It could save your motor. If you are running 7 psi and a few degrees ignition retard. 91 octane should be enough. Gasoline has a date on it. Kind of like milk. If it sits in the fridge for a long time it'll go bad and make you puk. Say with gas. If it sits in the tanks for a long time it can get inpurities in it and go bad. If the 94 isn't used often (like in my area) it'll run better on 93 instead of 94. Your best option is to use a filling station that gets hit hard so you know know the fuel hasn't been sitting around long. You hear horror stories about ppl being out in the middle of no where in some hick town and they get gas and their car runs like crap. That's why...