levicki :
Let me summarize those cases for you:
Let me summarize you: A fraud.
Honeycomb mesh is nice, but the most important things about a fan grille are to have a very large hole to solid ratio (better airflow) and to have a moderate distance of space between the fan and the grille (to ease the issue of the blade being too close to a hole, which causes noise and hurts airflow).
OK, now the best place to have a power supply is at the top of the case. That's because power supplies are meant to be part of the ventilation system. That's why power supplies are supposed to have a fan on the bottom, to pull heat away from the CPU. That's why Intel's engineers, who know more than you and I combined, specified the power supply to be at the top when they laid out the ATX tower format.
I look at these cases, I see a bunch of bad fan grilles, but not because the holes are square. The problems are the ones I described, the grilles aren't open enough and many don't have enough mounting hole offset between the fan and the grille.
Too small? Some people like small cases. Micro ATX cubes are still somewhat popular. It all depends on how you want to build your system.
The Cosmos S breaks the rule that it's almost always better to have the power supply at the top, but for good reason: It has a tripple-fan radiator mount at the top. You couldn't put a radiator there if there was a power supply in the way. So, in order to get that great radiator mounting location, you make the sacrifice in cable management, and end up with an extra fan to make a bit of extra noise. That's the price you pay to have a big radiator, but otherwise bottom-mounted power supplies are an idiotic idea that manufacturers are now providing simply to copy other manufacturers.
Give the buyer what they want, even if its stupid. Bottom-mounted power supplies are generally used for the same reason that the Inwin has a "futuristic trash can look": To entice ignorant buyers.