A friend of mine shotgunned a Sparks (I think it was only 8%) in about 6 seconds and immediately passed out on the couch and we built a fort around him with Cinderblocks. You gotta admire this guy's stamina.
A friend and I used to try to see who could drink the most Sparks (the original with caffeine). We could never get past 5. At that point you start to get chest pains and question your life.