The cheap 1.8 50mm is built horribly but is generally regarded as hugely good value for money. The 1.4 50mm is better built, a little better optically and has a better bokeh, so if you want to spend the money, that lens will probably be better in the long run.

So between the 85 and the 50, which focal length is better for you? The 85 is probably a better portrait lens, the 50 probably better for general purpose things.