Are you talking about the "Sofortüberweisung" ?
Even though they do not fraud (like using your TAN to make funny stuff),
it's an obvious risk you take.
Chargebacks are rarely happen, but they are known.
Consider it like "Paypal XS".
Thanks for the reaction,
Yes, it's the "Sofortüberweisung". They are the only company offering easy online banking services across multiple European countries. And they accept Bitcoin merchants.
Chargebacks are the main risk of credit card transactions, specially with an anonymous product as Bitcoins.
I understand that Paypal should also not be used when selling Bitcoins for the same reason.
Direct online banking is relative safe in relation to chargeback risk, because security measures like calculators and TAN codes are involved. When using the Dutch iDEAL system for online banking (over 95% of all online transactions in The Netherlands are with the iDEAL system, cooperation of all banks), there is almost 0 risk for chargeback. I don't know how this risk is like using online banking in other European countries. I believe the risk is much lower than with Paypal.
Inge