One of the issues with PayPal, that scammers will use, is to make sure you do one of the following:-
Wait over 90 days after you have paid before you complain - Its very hard to get Paypal to investigate after 90 days.
or as has just been done to me (UK Compnay....)
After I complained via PayPal that the goods haddn't turned up, the company emailed me saying that if I removed my complaint they would then give me a FREE upgrade and ship my item stright away. While this sounds great, as soon as you remove your complaint you CAN'T re-open it. I forwarded their email to paypal, and kept the complaint open, I was then refunded within 24 hours!
Regards