After buying my 2nd WSD bike (first was my road bike, now my MTB - A genesister), I found that the WSD fit was great for people like me -- shorter waisted, only 5'3" but longer legs (30" inseam). The fit on a WSD small works for me because the stretch length (along the top tube, seat to stem) just fits me better. If you have issues with leg length, you can work with the seat or get longer crank arms as an option.

Worked for me, but of course it will vary!!