One of the lens which i thought of for myself because of the versatile..
But if bokeh is the main concern, i think a lot of prime lens will win in coz of bigger aperature..
I think it depends on the focal length. 70-200 f2.8 IS at 100mm will create better bokeh than 50mm f1.4 I think. It also depends on the distance to the subject. I use both 70-200 f2.8 IS and 85mm f1.8, and I personally like the bokeh produced by the 70-200 better. But it's just me.