The name STeFan transcends the PH variants it owns "Stephan" and borrows "Stephen" due to spellings. It's the PH variants that could also be STEEV-ens as well.
The sad thing is there was a kid in my class named Stefan and every substitute would pronounce it ste-FAN instead of STE-fan and I felt really bad for him.
This name is a league of their own. Those with the name don't like to be associated with the English name Stephen the cousin name but not the same. The f element in Stephen must obey it's original rules from Ænglisc, the f is passive in the flow or at the end which is why My name is pronounced as STEEV-en.
The popularity chart lists Stefan as being pretty much at the bottom of the Top 1000 Male Names in America, but I'm seeing more and more boys being named Stefan! Must be mainly in my area. Anyway, I think Stefan is a wonderful name. I've actually always liked the nickname Stef/Steph more for a boy than a girl.