Well, so far, I haven't really sold any men's items in a big way except for the odd pieces here and there. There are men who told me to bring in men's g-strings. I asked my friends and they told me that men don't like wearing Gs. But then there are men who told me that they wear female lingerie, so what is what?
The preferred men's underwear in the United States is the boxers. Walk one round in one of the shopping complexes and you will even have a hard time looking for regular briefs.
Recently, I came across ergonomic underwear. Ergowear.com is an online store that sells ergonomic men's underwear and swimwear. Ergonomic underwear is generally targeted at men for obvious reasons.
I first came across the word "ergonomic" when I had the opportunity to test out an ergonomic office chair. It really does fit the body so well, it's like being one with the chair.
And to my friend who told me, "My balls big lahhh" in reply to my question on why he doesn't wear G-strings, perhaps ergo thongs is the answer for him.