They both seem to be equal in features, but the Lexa has much better cooling, so I would go with the Lexa since it also has a very unique design that works well. That said the Hush looks grotesque, so I would have to say you should pick anything but the Hush.
dont get the antec 900. has huge problems with dust and its very cramped once the system is fully built.
both of the nzxt cases are nice, so its really all up to your personal taste. they both seem like quality choices from the cooling aspect. i've owned nzxt cases and they're fairly nice in build quality.
with that said, the cooler master 690 is a very good case. its a bit heavy, but it has slots for up to 6 or 7 120mm fans. also, its really easy to keep the case tidy because of all the features it has for cable management.
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Q6600|2GB Crucial Ballistix Tracer|DFI P965-S Dark|2900XT|Raptor Main Drive|Audigy X-Fi|Rocketfish Case with H2O|