I looked at the photos of other "marketers" who had already committed and I decided to decline the invitation.
A large percentage of them looked like they were using a photo taken straight out of a police line up! I didn't want to be associated with them. They didn't look trustworthy, they looked shady. They didn't look like experts, they looked like fakers.
While it's true that you can't always judge a book by it's cover, it's also true that more often than not, success looks more like success than like a drunk being booked for public intoxication.
My 2 cents: Get a decent picture taken, or don't use one at all. Just don't put a "criminal likeness" on your marketing efforts because using a mug shot is surely scaring away potential buyers. It just doesn't look professional. It reminds me of a guy in a trenchcoat standing in an alley going "Psst. Hey buddy..." ...while trying to sell fake Rolexes to people passing by.