Received the 25/1.4 today - not much time to play with it but my cat was fairly obliging.
This is even sharper wide open than I remember although maybe the extra pixels on the GX8 help.
Both shots are RAWs loaded into LR and then exported with no processing (except cropping).
100% crop - focus was just at the edge of the left eye. My poor cat seems to suffer from weeping on occasion but the vet says this is OK.
I bought this lens from a grey-importer at about 2/3rds the normal price. The sharpness here would be about the same as my M8 with the Elmarit 90/2.8 or my (now sold) A7R + FE 90/2.8. Suffice it to say the m43rds solution is significantly cheaper, overall.