>>18503573 (OP)
Mustaches are always "in", in the sense that when the right man has one, it looks good. I don't know what you look like, but if you don't have the right face, it will never look good, plain and simple.
What is the right face? A broad, preferably short (not too short) chin, absolutely no underbite, and a wide jaw. That's that most important criteria, being handsome in the rest of your face is obviously important, but if you don't have those, don't bother trying.
Facial hair, like any component of fashion, is largely based on geometry. You use the shapes your clothes project onto your body to highlight your best features. A turtleneck shows off a long neck, a fitted shirt shows off a muscular chest, high waisted pants define long legs, etc.
A mustache can divide up your face, balance it, or completely offset it. A lot of people here are posting pics of Idubbbz as an example of a bad one, and it is for him. He has a narrow face, jaw, and chin. His mustache is wispy, which looks bad all on its own, but it's also making his top lip look bigger, which makes his already not large chin and jaw, look smaller. Suffice to say, a mustache is not best for him.
