Only the guys with new cars use premium the rest use the regular. I have been using regular gasoline on both of my cars and they run just fine. Now I have heard a rumor (more than once) that premium gasoline in DR is actually diluted with regular gas to some percentage by gas stations (not all). This is done to increase profits. The premium gasoline is not really as pure as you guys think it is.
AZB
if prem gasoline is not as pure as people might think,, imagine how the regular might be. You really cannot be sure 100% on either reg or prem then; one just have to watch out for car's performance and adjust, i guess (as they have said here).