Instead of a PIN that wipes the device, it would be much better to setup a special PIN that logs the user into a sanitized, completely separate profile with generated content of no practical value. This would create plausible deniability, and be sufficient to allow low-level border agents to look through a phone and pass any checks without raising these kinds of alarms. The wipe PIN should still be an option, but should be separate, and only be for cases where you suspect a forensic imaging or search of the device is to take place and the legal consequences outweigh the risks.