Wells Fargo is a bigger target, but they also have many more layers of protections and an interest in providing customer service. My hunch would be that it would be easier for a criminal to profit off of attacking WF than attacking a personal bitcoin user, but that it would be easier to actually cause financial harm to a personal bitcoin user (even without profiting themselves). But to clarify that, I have a couple of questions about how storing your own bitcoins works, since I've never used it:
* How does bitcoin storage work with offsite backups? If someone compromised the backup, would that give them access to your money?
* If you lose the file (hard drive crash, home burns down, backup system fails, whatever), does neither you nor anyone else have that money anymore? I.e., someone wouldn't have to gain access to the money themselves to deprive you of it?