The two things you might consider changing there are the supply and case for two separate reasons.
1) By going with an adequate maybe a little heftier supply you allow for later expansion and upgrade. For a little bit you can move into the 500-600w range with the OCX 600w supply seen at Newegg.com - OCZ StealthXStream OCZ600SXS 600W ATX12V / EPS12V SLI Ready Active PFC Power Supply - Power Supplies
The GameXStream is the better series for OCZ however while another one to consider is the Antec TP3 550w model seen at Newegg.com - Antec True Power Trio TP3-550 550W ATX12V SLI Certified CrossFire Ready Active PFC Power Supply with Three 12V Rails - Power Supplies
The rest climb in price from $69.99 upwards.
2) That model sees a small 80mm front intake and a 120 rear for case fans. That doesn't offer much intake if you game a lot or run a lot. The alternative model also by Cooler Master would be the model see with three 120s one in front, one rear, and the additional third seen on the side cover. All three are led. Newegg.com - COOLER MASTER NV 690 NV-690C-KWN1-GP Black SECC/ ABS ATX Mid Tower Computer Case - Computer Cases
Run a pair of the exact WD sata drives here by the way. No complaints so far.