I use Paypal for everything I sell and buy on eBay, and quite a few other sites as well. I've never had a problem (knock on wood!) with them.
They've gotten me a refund when the seller did something shady (like send me an obviously used item advertised as brand new) and I have yet to have a problem with a buyer not paying for or receiving a refund for an item that was already delivered.
The only thing is, you do have to be fairly reponsive with them, watch your account for incoming disputes or if you yourself need to file one, and explain yourself clearly with data to back up what you're telling them.
If a buyer claims you never sent them an item, and you provide a tracking number or delivery confirmation that indicates it was already delivered, it's a non-issue. But if you skip that service to save the $1.50, it's possible Paypal will decide in the buyer's favor.
It's a good idea to get delivery confirmation on EVERYTHING you send out if you're mailing from home, or at least keep postal reciepts for everything you mail from a post office.
Another nice thing about Paypal is that if you get their debit card, you can withdraw your money from any ATM the day it shows up in the account.
I've heard the horror stories about Paypal too, and it made me hesitant to use them at first--but considering the way I've seen some sellers conduct buisiness on the web, I wonder if it isn't just Paypal laying the hammer on sellers who have irrational expectations of their buyers.