I pick Kozmo because, though I love both decks, this one is much stronger. It can easily get over whatever you throw at it and it's so easy to OTK/FTK. If you can get the right cards you need, the duel can be over in 1-3 turns. To add on to that, there's really no such thing as a bad hand with this deck. Each hand you draw, is just as useful, if not more useful, than any other hand you might draw. Plus, it's effects are nearly unbeatable. Most of the bigger monsters (Kozmo Dark Destroyer and Kozmo Forerunner for instance) can't be targeted, which means you could keep them out for a while, and when they're (the bigger monsters) are destroyed, you get to banish them from the grave to summon a new monster with a lower level to replace it from the deck. Not to mention the ability to summon as many monsters as you want in one turn using the effect of "banish this card to special summon a level ? or higher Kozmo monster from your hand." This is where the OTK comes in. Recycling is also easy at the cost of a few life points. With Kozmotown you can add any banished Kozmo monster to your hand for the cost of the monster's level x100 in life points once per turn. Then, if you don't like the current Kozmo monsters in your hand, or don't need a few of them, then you can replace them with Kozmotown. The field spell is practically Magical Mallet for Kozmo monsters and just like it's other effect, it's once per turn. This decks only real weaknesses are usually Kiajus, Burn decks and FTK decks. Monarchs on the other hand, can have bad hands and are usually only truly useful if you can manage to get out Domain and March of the Monarchs, or at least Monarch's Erupt, which renders most of your effects useless. Plus, unless you can get a smaller monster or at least Monarch's Stormforth, then you'll have little to no hope of ever getting out a monster. Kozmo's don't have this problem.