I would say the same thing that Kollision said...
The fun that you had with OutRunners and your childhood memories don't make the game be "9. Excellent on every level, usually only flawed in a single, minor area.".
The scaling is awful, in some parts you really don't know what that track-side objects were supposed to be and some seem to be flying or something.
The sounds are very annoying during the game (those distorted screams all the time are really bad...).
In several aspects, the game is a step down compared to OutRun, that was released 3 years before.
The review text briefly mentions the forced split-screen problem and the graphics, but overhypes about the voice samples that are more annoying than anything after you start playing.
You said that the forced split-screen is the reason to detracted colors when compared to the other OutRun games. However, IMO the main problem is that it implicated in very few other cars in your way even when you're in single-player mode. And that makes everything more boring.
I also don't see enough reasons to sell the game to your readers like that: "This game, in my opinion at least is the best racer in the Genesis library. "
Maybe you could say "The funniest" based on your personal experiences but to say that it is "at least the best" implies lots of things and I really doubt that OutRunners can stand for them all.
And I can tell you that I tried this game several times with different friends... They all looked at me, after 10-15 minutes of playing, with the same "save me from this nightmare!" face.