The Antec 300 is a very popular case with gamers on a tight budget. Ventilation, airflow, and cooling are excellent. The itnerior space is a bit cramped.
The Coolermasr Storm Scout is a larger case. Ventilation, airflow, and cooling are excellent. It is wider than the Antec 300 and can accomodate the 160mm tall cpu heatsinks. It is also longer than the 300 and can accomodate slightly longer video cards.