How long would it take you to guess 10,000 times, expecting that it might only require 5,000 guesses to find it? Is your data worth that much time? Remember that if you have the device set to wipe after 10 incorrect guesses, that won't matter at all. I think you can restore it from iTunes without the passcode. If the phone is backed up to iTunes or iCloud, you can restore it from backup. If not, you'll have a minty fresh new iPhone.