[quote name='bubbafett4hire']To the OP the bigger question is do you want a Slim or a Phat , Hard Drive size means nothing as on Sony's site gives you instructions on upgrading the HDD to a larger size.[/QUOTE]
HD size matters. Yes, you can upgrade, and you're not bound to a specific PS3 line so yo have many, many size options. You still have to spend extra to get a new drive, make sure you get one compatible with a PS3, backup your current drive, bust out the screwdrivers to make the switch (being careful not to strip the screws, which I understand is easy to do), then reassemable the whole thing, install your backup, and hope it worked OK.
That's an awful lot of work when you can just spend andother $50 to get a system with another 40gb from the get-go.
Unless he just really, really hates the look of the slim, I don't see much reason to get the phat. (and I do prefer the look of the phat.)