Well there's not really much more to ask than the title, so which way should fans blow?
Best Answer
The point is to remove heat from the case so:
heat rises, so fans at the top of the case blow the hot air out and fans at the bottom blow cold air in.
fans near hot components (CPU, Power supply, high end graphic cards) blow air out because you want to remove the hot air - not spread it around.
you have to have good airflow where hot air is continually removed and replaced with cool air - so, fans at one side (usually the front) blow air in while fans on the other side (back) blow air out.
The design of the case looks to have gaps around the front panel to allow air to flow into the case. As such, you shouldn't need to have the front panel removed whilst the machine is in operation (I'm sure they wouldn't have put a front panel on there if it was seriously detrimental to the operation of the machine.) With the panel in place I suspect the machine sounds slightly quieter and looks neater.
That said, you could easily conduct your own tests of this, by monitoring your system temps whilst the machine is in operation both with and without the panel in place. I would always suggest doing this after a new build anyway to be sure the cooling in your machine is sufficient and heatsinks are correctly seated.
Best Answer
The point is to remove heat from the case so:
heat rises, so fans at the top of the case blow the hot air out and fans at the bottom blow cold air in.
fans near hot components (CPU, Power supply, high end graphic cards) blow air out because you want to remove the hot air - not spread it around.
you have to have good airflow where hot air is continually removed and replaced with cool air - so, fans at one side (usually the front) blow air in while fans on the other side (back) blow air out.