I heard of Antec as quality cases before I even found this site. I was in the market and needing a cheap case - was between Cooler Master and Antec.
Luckily - I was able to find a Microcenter within driving distance and I was able to tinker with each case in person to see how they're all built. I ended up buying the Antec 300 - based on reputation - and price - and it's got very good airflow - with room for additional fans - for the price. The 900 has a big ole fan on top - that would be nice too - but for my needs - the 300 works fine.
If I were going with Dual Video card - and really heating up the insides - a 900 would probably be worth the extra money for a larger fan on top. But I'd rather spend the extra 50 on something else

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When you have your selections narrowed down - you can see some pretty thorough reviews on Video on Youtube. Gives you a better picture of spacing / feature / functionality - when compared to a feature list and photo.