I don't really know as I've only been in a handful of them. However, I've found that I do pretty well in worlds I don't commish(I attribute that to looser recruitment standards and lesser win requirements). So, between the two I commish, I find MG to be more challenging. I'm .523(12 playoffs in 22 seasons) in MG and .513(10 for 20) in Coop. I've had 6 season of "dry spells" in both. I know the math doesn't agree with me but I'm currently mired in the MG dry spell so it just seems more difficult right now.