Ok that question is a little unfair, but I'll answer it. The thing to keep in mind is that the JtO model is a combo model, so the design was very limited and they had to use the pieces they had.
The Overlord model has none of those shackles and was completely up for John Ho's creative ideas.
So I believe the Overlord model is superior. It was designed by one if the best Lego designers ever. However, the JtO model is a fantastic combo model and I'm not sure if John had to make a combiner his would look much different.
Bottom line is if you're willing to pay for a Makuta, and you can only get one I recommend ordering the parts for Overlord. I don't want to talk about my thoughts on him too much yet, as a video review is coming.