Seems that GE requirements are rather arbitrary...
I was denied, twice. I have a DUI misdemeanor conviction from 2007. I, of course, disclosed it.

Here's the kicker (and the agent got a kick out of this too when his boss told him to deny me): CBP and the agency I work for are in the same department. I hold a valid security clearance. No disciplinary action was ever taken against me by the agency for the DUI conviction, never had my access even suspended for that, let alone lose the clearance. According to the agent, sure... in his logic, based on a simple fact that gov't would trust me with secrets I should've been granted GE membership. His supervisor disagreed.