I guess to each his own – I live in South Florida, and I can tell you men here do not usually wear undershirts simply because it's too darn hot and humid. I never have, and I never met with a partner who did, either. Different cultures for different places.
Back on topic, Brooks Brothers slim fit is the best in my opinion.
Brooks Brothers makes excellent shirts….i recommend the extra slim fit non iron dress shirts. I bought quite a few last year when they had the huge annual sale. I have Express shirts too (extra slim fit) and they are nice but not quite as good of quality and i like the non iron that BB has to offer. Express shirts do come a a nice variety of colors.
As far as an undershirt goes, if you wear a dress shirt unbuttoned at the top, DO NOT have an undershirt showing. It looks tacky and unprofessional. We are not in fifth grade anymore. I understand you dont want to have chest hairs hanging out but you can take care of this another way. My recommendation for you if you MUST wear an undershirt is to get the low cut vneck ones hanes or a similar brand offers. You get the benefit of an undershirt yet you dont look like a complete stroke.
@Beavis is right on! Undershirts should not be showing, that's men's fashion 101. And I totally agree, if you have to wear one, it should be a V-neck! That, or just groom!
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