The biggest scrotum poppers I see coming in for interviews (anywhere) are the college-aged kids who have the scraggly hair and the 'chinstrap' of facial hair to go along with dad's suit which doesn't fit. Or, it might be a diamond earring, greasy spike, & untrimmed goatee. The idea behind being clean cut is that it conveys that you aren't a piece of sh1t who's going to have problems waking up before 10 am, who would repel affluent clientele by looking like you just rolled in from the frat house. The specific style isn't important, just look clean. Military cut is OK if you don't have any distracting oddities (major scars, large moles, really bumpy head) on your dome. Just be aware of what others might find distracting.
Talking to other business owners, I'm never ceased to be shocked at some of the people that come in for an interview whenever a job is offered - at any skill level. Unemployment might be high in some areas, but a big part of that is the number of grossly unemployable people out there. Who wants a 300 lb receptionist, or a complete AFC basketcase on their staff?
Look clean, you'll be fine.