I dunno. Providing the banking sites don't require anything too advanced (eg must have CSS or javascript 1.3+) I can see that they should work.
Most of the recent phishing style fraud would likely affect any browser that has a sufficiently developed javascript implementation - it's more a site vulnerability than a browser one.
As soon as gecko, kHTML etc are ported for amigaos we'll have as many browser vulnerabilities as the next system (although far fewer problems at an OS level).
