This needs to be a tournament. Frankotank, would you mind if I made it a tournament? (Or you can run it.)
My top all time cereals are:
Cracklin' Oat Bran - great out of the box or with milk, but perhaps the most unhealthy adult cereal ever
Cap'n Crunch with Crunchberries - great mostly out of the box, but good with milk as well.
Apple Cinnamon Cheerios - great mostly out of the box, but good with milk as well.
Honey Bunches of Oats (classic flavor) - great with milk, soso out of the box.
Raisin Bran - great only with milk, not very good out of the box.
As a kid and teenager I loved Fruity Pebbles and Frosted Flakes, but I haven't had either of them in years. I'm not sure they would translate to adult tastes.
In the final seven games of the 2013 season, the Chiefs averaged 34.6 points per game, scored 38 points or more 4 times, and went 2-5. The NFL has ruined the sport.