Migrating Hosted Exchange Account (GoDaddy) to Office 365

Evening all~

I am over my head so far with the whole migration thing.   I have one mailbox (10 GB) that is currently hosted on GoDaddy.  I have set up a Office 365 account to host the mailbox in lieu of GoDaddy.

Questions

1) What are the pitfalls of exporting the .pst from the users current desktop outlook and then reimporting the .pst into the new )365 mailbox?   I have read that some items may be locked (read only) or that you can't respond to original emails.

2) Why should I use MigrationWiz versus just import / export for this one mailbox?

Thanks for any help-

Benjamin