I bought this lens when looking for the later f1.7 version. However, I'm very happy with this lens and doubt whether the f1.7 version could be much better. It's now one of my favourite lenses. Here's a couple of shots taken at f1.8 and f2.8, with 100% crops. Camera used was A7rii with K&F Concept adapter. Great bokeh, and the lens is pretty sharp considering it's made pre 1966. Corners are good too, though obviously not apparent on these shots. If anyone is interested I'll post a couple of shots showing the corners.
f1.8
Minolta Auto-Rokkor PF f1.8@ f1.8 by Jon, on Flickr
f2.8
Minolta Auto-Rokkor PF 55mm f1.8 @f2.8 by Jon, on Flickr
f1.8 100% crop
Minolta Auto-Rokkor PF f1.8@ F1.8 by Jon, on Flickr
f2.8 100% crop
Minolta Auto-Rokkor PF 55mm f1.8 @f2.8 by Jon, on Flickr