Hi welcome aboard.
Both good lenses, image quality are both very good, personal preference for focal length is the thing. I much prefer the 85 1.8 over my 50 1.8 that I have, but I don`t have the 1.4.
On my 7D so same as your 60D, I don`t like the focal length of the 50 and the 1.8 is horrible to use. Maybe that is why I dislike it so much.
If I was to try a portrait shot I would take the 85 and the Sigma 30 1.4.
Canon 85 is nice for tighter shots, the 30 for wider full body portrait. The 50 seems to get lost in the middle, but like I said at the start its personal preference.
Have you got other zoom lenses, try using them at setting of 30, 50 and 85 and see if that gets you what you need.
Canon Powershot S95, Canon 6D,7D, Canon 40 2.8 STM, Tamron 24-70 2.8 VC, Canon 17-40 L, Canon 15-85, Canon 85 1.8, Sigma 30 1.4, 50mm 1.8, Canon 100 2.8L Macro, Canon 70-300L +Kenko 1.4 Pro 300DGX, Canon 430EX II and RS 4 Classic