I'm one of the unlucky ones who had a bad experience with paypal. I sold an expensive item on Ebay and received payment by paypal. I posted the item off and as usual I obtained proof of posting. Six MONTHS later the money was taken back out of my account by paypal. They said the buyer had claimed her credit card had been misused (not stolen, simply misused) by someone else. To add insult to injury, she also claimed she had never received the goods. A few days before paypal robbed me, I'd had a clear out of old paperwork and binned the proof of posting, so I lost out completely. What really grieves me is that the item I was selling belonged to my late mum and had sentimental value. I sold it very reluctantly as I was desperate for the money at that time.
I wouldn't touch paypal again for all the tea in China.