I believe this question is only answered by two kinds of people. The first live far away and can watch the awfulness unfold in relative safety, participating as if being an arm chair scicaro's was something cool, picking side as if it were a ball game. These people really need to look inward because they cant see that they are metaphorically grinning as we all watch the destruction of a culture. The real question they should ask is, "Do I really understand what is happening? I don't see how after coming here and becoming as informed as we become could we answer this question legitimately?
Then there are those that are stuck in the middle, being protected by one group or on the receiving end of another. I truly feel for these people, they have no choice but to see one cartel as better than the other, or one worse than another, this in turn just continues the fracturing of a society. It's what happens in Central America all the time, one neighborhood against another locked in a never ending cycle of reprisals. You take care of your own and whoever is attacking is the enemy. If one really thinks about this question it is a trick, no cartel is good so why would you pick any? Only if forced in to the decision can one truly "pick teams." If an entire government is corrupt then what use it it picking a political party? The same could be said of the cartels.