I cant really do a comparison between the 2 since i have sold my cneturion 590, and i can say the antec has much better qualiity than the M9, and much better cooling as well with the PSU on the bottom, the antec doesnt look like its only 60 bucks, the M9 looks cheap and feels like a 50 dollor case, the centurion is much better than the M9, if your shopping for a case in this price range, look no futher than the ANTEC, or the 590, both are great cases, but i personally like the ANTEC a bit more, but very close between the 2, build quality on the 590 and 300 are MUCH, and i mean MUCH, better than the M9, i have built many systems with these cases, they are best sellers because of the price of the cases.