Were you asking us or telling us? I think many, including myself would disagree with the "best" part of the title.
Hot air has a natural tendency to rise. - so you are pushing the hot air inside the case in a consusing manner, with one top fan pusing into the case, the other pulling out. That would cause turbulence and impact the overall airflow. - it's also directly against the fan (blower or open fan?) of the GPU - (if we can believe the diagram). Most people that care about cooling have blowers GPUs that vent the hot air to the back. Your diagram shows a open fan setup that blows the hot air from the GPU directly into the down push of the top fan.
So yea, not the setup I'd ever build in any computer I put together.