Glad someone dragged this one back to life.
Personally I think the Z3 is no more "girly" than any other small sports open-top, although it doesn't strike a roughneck pose like, say, a Lotus Elise does (yet talk about a "girly" name for a car). It's not even as cute as the MX-5 Miata, and I don't think that car's particularly "girly" (look at how many older, middle-aged men drive those if you don't just want to rely on one opinion). If there's any BMW "Z" that I'd consider girly, I'd pick the E85 Z4 long before the Z3.
I never thought of the Z3 as a great-looking car, though I can see why it has its advocates.