I here what your saying but what if due to some typo you meant to pay $100, but the typo was $10,000.00 so your just out $10,000 due to a typo? You can't believe thats fair? If that really were to happen you still have no recourse through Paypal. A CC company would never allow this.To be fair, PayPal doesn't force you to use bank transfer. They default to bank transfer, but you can always switch to credit card per transaction manually. I do that hundreds of times a year because I never ever use bank funding through PayPal.
Second, your situation is a tough one for PayPal to protect against. On the other side of things, as a recipient of funds, I wouldn't want a buyer to be able to dispute a charge after the fact on the basis that they typed it in wrong. Non-delivery is one thing, but typos are a different story. Again, to PayPal's credit, you have to go through a few steps of confirmation before a payment is sent. You DO have a couple opportunities to double check the amount.
Finally, with payments by CC, you can, as far as I know, start direct chargebacks if PayPal doesn't help you. PayPal doesn't like that, but your CC issuer will typically help anyway.