Your ebay experience obviously depends on the seller. I've been using them for about 10 years, and this is the advice that I'd give:
Only buy from someone with 100% positive feedback. The best ones have between 50-1000 reviews, because they will bend over backwards to protect their rep. You may think your safe buying from someone with 99.8 positive feedback with 50,000 reviews, but your negative is just a drop in the bucket to them.
Use paypal, but also use a credit card with a customer friendly charge back policy. If something goes wrong, you have multiple options for disputing the charge.