I've seen it used by others for years. And opened several cases that smelled like Zippo fluid as late a week after it was used in them. Sure, no sticky residue, but if you can still smell it, that means it has either accumulated in or between components, or it has infiltrated the insulation.

On the other hand, denatured (unless you just pour it in there) is gone in under five minutes. No scent, no muss. And it doesn't weaken as many synthetics as petrochem-based agents.