Hey Khalee, I'd say go for the $80 600W monster. I have seen this manufacturer, MGE, lately around stores and webstores. But Nemesis is right in that Antec is one of the most reliable makes around. Another manufacturer that makes some cheap 400-500W quality power supplies is Thermaltake, believe it or not. I always thought they were expensive as anything, but I put a $40 400 watt unit in my boy's rig and it's been around a year or so now and runs well. I bought MGE's 400 W (or was it 450?) unit for another system I am building, but it's not built yet, so I can't really say how good it is yet. But they are beginning to appear in many places.
Also, read, with huge grains of salt, the customer reviews in the webstore sites, like Newegg or etc.