Paypal is good for standard stuff. Now, if someone applies for a refund, or the credit card used is stollen or the owner cancels the transfer, (and the buyer does not have funds in the account) the seller will never see the money...but it has the subscription option, which is good for membership stuff.
You can get your money to your bank account fairly easy.
For safer transfers, I have experience with e-gold and MoneyBookers.
E-gold, no refunds, no claims, safe transfers, but hard to get funds and get money of your account: have to resource to third party processors...heard that recently these third party are not all accepting e-gold anymore...
Moneybookers, credit card verification, extremely safe. No refunds (only through direct deposit, meaning, no refund button as paypal). You can get your money back to your bank account. They have a limit for transaction (due to money laundry protection, I think), that can be increased if you verify a bank account and credit card). My favorite for safe transactions to the seller.
If you plan to offer an easy way to pay with the credit card to your clients, I sugest 2CO. They automatically verify the payments with their fraud control. Not 100% safe, but still good enough for sales up to 30-40 dollars. They directly deposit on your bank account on a weekly basis, but they need a minimum 300 dollars earnings to process a deposit.