True but I've got PS+ and a few games I need to finish.
There's the "problem": PS+. Indeed, with the recent Sony E3 give away, that chews up HDD space. I am on the Phat 80GB model, and still have 10GB left. Then again, I don't have too many games nor a PS+ account.
Let us know which brand of HDD you are going with (I gathered it will also be the 5400rpm type to keep the cooling down).... I bet in about a year time, continuing with the PS+ account, even the 500GB would not be enough.