R=RON=Research Octane Number= tested at 600rpm M=MON=Motor Octane Number= tested at 900rpm basically, it sounds like they are taking an average of what should be there and what it's acting like.
Because of misinformation. If it is stock depending on the car all pump gas should work fine. Octane booster should only be used on modified cars, and really octane booster that is bought in stores is not all that good. Tulene is much better and it is basicly octane booster and it can be bought at paint supply stores and use safly as an octane booster. But the best thing to do would be to just buy high octane gas, just get a barrel of it and get a manual pump. Then again that is pricey, so what my roommate does is he has a can of tulene paint thinner and adds a few onces to the tank just before he Auto-x's. He has a mixture that he does, I will post it up when he gets home. Edit: I found the link to the mixture he uses: http://www.elektro.com/~audi/toluene/