I have been wondering the same thing here recently. The cases I see two problems with, first you don't get the best looking case, and second its only about $200 for the case setup. A basic kit will run you $200, and I am a firm believer that you get what you pay for.
I've heard some good things about the Koolance cases, but I think I would stick to either a kit from a reputable company, or just buy individual parts.
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