my daily travel distance is around 80km too and sometimes during weekend, I rode my bike for 152km per way to my hometown. Iam using Corsa Sports Rain

front: 80/90r17
rear: 100/80r17

this model has better performance than S123 in wet road conditions but S123 may last longer than Sport Rain

Date: 21/01/2016 ODO: 26,156km
change both front & rear tyres

Date: 02/10/2017 ODO: 54,751km
change rear tyre only because front still got > 70% thread

Date: 30/05/2018 ODO: 66,354km
as of today rear still got > 80% thread while front < 25% and need to be replaced soon

for my usage, rear can last about 28k km while front can last about 40k km

so far so good