Just a quick overview of both models. The SCPH-1001 can be found on eBay as "Rare" or and "audiophile" model. The truth is that its really not. Its just a typical launch model with a few bugs that Sony corrected in every revision after the 1001.

I was under the assumption that the 1001 was the "best" revision of the PlayStation, after receiving a free 9001 I realised I was wrong about that. They're all similar.

If your looking for a PlayStation its a safe bet to purchase any model after the 1001 since it will be a more reliable system.