I really like wearing an underwire, though I know some people find it uncomfortable. With an underwire, I feel like I get more support. Though, now that you mention it, I'm not entirely sure that's accurate.
I hated underwires growing up because they were uncomfortable, so I didnt wear them for a long time when I probably should have been. Now that I have tried them I love them because the support is so much better.
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Finding my muse
I only wear underwire. As long as you find one that is made correctly and fits you right it shouldnt be uncomfortable. There are so many things about bras that would be non issues if bras were just made better.