My iPhone 4's home button has become flaky. I'm thinking of taking the phone in and see if they'll exchange it or fix the problem. My question is, does Apple let you do a device wipe before you surrender your phone to them? I'd rather not all my personal data be accessible the Apple Store employees once they have my phone in their hands. Basically, I'd like it to go like this.. I demonstrate the problem to them, they agree to swap the phone (or whatever) and I do an "Erase all content and settings" right there in front of them before I surrender it. What can I expect?