Why choose full frame?

[Brazo]

Both zeiss Harry?

If its for portraits I'd go for 85mm as the fifty is still a fifty on crop albeit with the middle cut out, you don't get the focal compression you think you'll get I.e it doesn't look like a 75mm

 

[sneeks]

Do you use the 50 much considering you have the 16-50? I'm trying to decide which fast prime to get, leaning towards 85mm 1.4, but wondered if the 50mm 1.4 would be a better option.

I only ever use the 50mm when in low light situations where I could benefit from the wider aperture it offers over the16-50mm. I prefer the 85mm though as it gives a much more pleasing look to portrait photos.