Again we have a low budget company that believes that it can offer rebates, but never actually honor them. NZXT is one of those companies. After almost four months and numerous emails, NZXT continues to drag their lazy a** and even stated, "well if you read the rebate, NZXT has no real obligation to honor our rebate offers. What a slime based company! If I were you I'd stay as far away from NZXT products and don't expect for them to honor any of their rebate offers.
You summed it up in your first sentence - they're a low budget company. Most of their cases aren't of very good quality and are copied from designs of better companies like Antec who have much better quality and customer service.