I am a little embarrassed to realize that it has been over a year since I was reading this thread (and a little surprised nobody else has added to it in the meantime). But I guess I needed some time to let the concept roll around in my mind before diving in to give it a try...
Not that long ago, I bought my first women's bikini bottom. I guess the posts here got me curious about it. But then, I was doubtful that there would be anything decent and masculine-looking enough that would even fit me... but I was surprised and pleased to find that Speedo does have women's sizes that go large enough.
I have not worn it in public, as I am way too fat to wear a swim brief -- I still enjoy my jammers and rash guard for swimming -- but once I lose my weight, I do hope to get up the nerve to do some swimming in various swim briefs.
So... let me know what you think of this suit.

Speedo PixelPalm Hipster Bikini Bottom by
C J, on Flickr

Speedo PixelPalm Hipster Bikini Bottom by
C J, on Flickr