So I have had the new Sony/Zeiss 50mm f1.4 for about week and I wanted to share my thoughts on it. I also have the Sony/Zeiss 55mm F1.8 and the Loxia 50mm f2.0 so I have compared them all. First off I'll say that the new sony 50 1.4 is big and heavy and I don't like that. It's heavier than the Sony/Zeiss 35 1.4 but not really any bigger(It is a tad wider). To me it doesn't feel very good paired with the A7rII and it looks a bit ridiculous on the camera, especially with the lens hood attached.
Image quality wide open is great! This the whole reason for this lens to exist. Nice smooth bokeh with good subject separation. I really can't find any faults with this lens at wide apertures. Stopped down the lens is good, much better than my experience with the Sony/Zeiss 35mm 1.4 that truthfully sucks when stopped down but wonderful at f1.4-2.8(I have tried 3 copies). The 50 1.4 is not as good as the Loxia 50mm stopped down at 5.6-f11 range. The Loxia shows better micro contrast and sharpness stopped down for landscape type work. The difference is not huge and if the 50 1.4 was the same size as the loxia I would choose to only have the 50 1.4, but it's not so I'll keep the Loxia for landscape/cityscape type work. As compared to the the 55 1.8 I would say that the 55 1.8 is as good and may even be a better all around lens. It's smaller, lighter, produces great bokeh, character and is strong stopped down and wide open. But I never got comfortable with the 55mm because the field of view always felt a little confined to me. 50mm captures 20% more area than 55mm. I never thought 5mm would make that much difference but I enjoy shooting at 50mm more than 55mm. So I may sell the 55.
So for me I'll keep the 50 1.4 and it paired with the 35 1.4 will be my combo for event work and environmental portraiture. These lenses really do produces a wonderful character in images at wider apertures. I'll probably shoot at 1.4 90% of the time.
I hope this helps anyone who is considering lenses in these focal lengths for their sony A7 series cameras. On a quick side note I picked up a old Minolta 58mm 1.2 on eBay a few months ago and adapted to my A7RII and this lens is a little soft at f1.2 but it produces some stunning images with jaw dropping bokeh at f1.2. you can see some examples here
https://www.flickr.com/photos/jhemp_00/albums/72157669978190420. I also have other albums for different sony lenses with examples. Probably after a few more weeks I'll be posting examples of the 50 1.4 on Flickr.