I sell lots on eBay, and have been since 1998. Never had an issue. The 10% in fees, to me, is worth the buyer/seller protection eBay and PayPal include in the transaction. I've sold every iPhone I've ever had since 2007 on eBay, as well as a couple of iPods and iPads. Never a problem, and there's a huge audience and potential buyer pool.
With craigslist, you're literally taking your life in your hands. I have no intention of ever meeting in person or exchanging cash to conduct a transaction - it can be very dangerous.