19 to 20 = Exceptional. I would fly to eat here and have no trouble spending a day's pay to dine here.
17 to 18 = Excellent. Driving two hours to eat here, would be time well spent.
15 to 16 = Very Good. I would miss a Chicago Bears game to eat here.
13 to 14 = Good. I would recommend eating here.
10 to 12 = Average. I would or would not eat here again. It would depend on my company.
6 to 9 = Poor. I would not eat here for free.
1 to 5 = Very Poor. I would not eat here if you paid me.
I will usually give two ratings. One for a score versus similar type restaurants, for example writing a review for Il Forno and then comparing Il Fono vs Biba as well as an overall dining experience.
I think this gives a better picture. For example Squeeze Inn vs all burger joints I would give an 16/20, but overall a 13/20 vs the overall landscape of restaurants.
Wine: I will usually comment on wine, but I think good wine can make a good meal a very good meal. It cannot though, make mediocre meal better.
Ambiance: I will comment on this, but not score it. There are some gems that are just holes in the wall, but serve good food.