Since I have rarely come across a beer I do not like, (MGD falls into this category, and that is all), I have a "drinkable" rating system.
1. Skunky - This is what MGD is to me
2. Somewhat Drinkable - the name speaks for itself. Something you power through. For example, Hamms when camping is a "very" drinkable beer, however at home it is falls under the "somewhat" category.
3. Drinkable - A decent tasting beer and seems to disappear. Most beers will fall into this category. Classic drinkable beer, High Life.
4. Very Drinkable - A beer that you have a hard time putting down. You want to savor each sip, but the taste is so great, you tend to drink faster. Not that anyone else agrees with me on this, but this is where Kokanee, Moose Drool and Trout Slayer fit in.
Side note, I did not realize that Labatts runs Kokanee now, interesting.