I see Midnighter doing slightly better than Taskmaster. Which is to say, he's going to get his shit rocked. He's got nothing to put Wade down fast enough that his healing factor or ludicrous durability can't compensate for. He can't predict his moves, since nobody in Marvel can read his style or what the hell he's going to do next. And Wade might honestly be a better fighter when he's not dicking around. Plus, his banter will throw MN off his game.
Midnighter might get lucky, but I can't see him winning if DP gets serious.