Spin Gal,
I'm a 5' 4" woman who started with spinning and ended up with a men's road bike. The WSD geometry is great for some women, but body proportions have a lot to do with it. I have the typical relatively long legs and short torso, but I have long arms. Both Trek and Specialized men's bikes worked well for me, as they had slightly shorter top tubes than many of the other brands' men's sizes, but weren't as cramped for my long arms as the WSD models. If the only drawback is too-long reach on the shifters/brakes, Specialized makes a $10 set of shims that can take care of that problem.
So, keep an open mind on WSD vs men's geometry, and see how the test rides feel. And good luck!
Dagna