I wouldnt compare the RealPower 350 you get packaged with a case to that CoolerMaster RS-450-ACLY listed on NewEgg.
The CoolerMaster RS-450-ACLY is a much better power supply with features such as Active PFC and ATX12V V2.0. Just read the reviews that New Egg has listed under "Resources Review From ". I bought this PS and would recommend it, particularly, if your looking for something with updated features for the newer MB's.