This is actually tougher to decide than I thought. I was gonna give it to AC based on size and firepower, but considering the past of Transformers and their ability to change form, it gives them a distinct advantage. Also, if we put aside the animosity between the Autobots and Decepticons, and especially Optimus and Megatron, the 2 of them alone could tear up some serious AC ****. If the Transformers (ALL the Transformers) manage to work into a cohesive fighting unit, they have a real chance. Another thing in favor of Transformers is that they're all individually unique in weaponry and personality. The ACs have differences, but they're also very similar in a lot of aspects. If the TFs figure 1 out, they pretty much have all of them figured out. And with tactical planning abilities possessed by some TFs, this could be exploited to the fullest. I can honestly say I'd have to see this fight play out to see who wins. I think the terrain in which they fight is also very important. The more I think about it, the more I have to side with Transformers, even though a LOT of things have to go their way.
............."We're gonna see just how much Rod they can handle!"............................................."Not all those who wander are lost."