Yes, they "make" PSUs. I've only read one review of their units, and it wasn't kind. I looked up a review of the unit in question. It has bad efficiency, and can only output about 360W. They couldn't pull the full 450W. It's actually made by delta, so it had good ripple, etc. And unlike cheap units, it shut itself down when they pulled more then ~360W instead of passing bad electricity. I'm not sure if ~360W is enough for the 4850 and whatever else you might have. Toss in the poor efficiency and you might as well just buy a better unit.
D@mn, guess I gave the long answer after all.