It appeared that regardless of having carry on only would have made any difference as everyone had to stand in that same line to go through customs. So the only advantage you would have is not having to get your checked bag...which wasn't what took so much time since our luggage had plenty of time to get there during the approx 3 hours it took us to get to it.
So, do what would be easier on you to handle and navigate...but do check with your airlines and be aware that luggage bins may be at a premium considering how full flights are. Best of luck.