Just make absolutely sure that you try to contact the person you sent money to.
I had someone start a dispute without contacting me about the problem. Paypal took the money out of my account immediately.
I contacted the guy within a day as he had given me his work address to mail it to. He recieved his item a week after the dispute, never cancelled the dispute dispite my urgings(all he would do is post in the dispute for paypal to close it), and paypal gave him his money back when the dispute time ended. and he still had my item. Paypal cant seem to contact the buyer, nor can I.. and they will not do anything about it, even though a LIVE person never reviewed the case before the case was closed.
There are two sides to every story, just make absolutely sure to do your best to contact the seller first before disputing. It may be a simple mixup that can be handled without ripoffpal automated dispute system getting involved.
(I have been on both sides of the story with Paypal, and disputes never end well for me.)