K-70 is a great camera at high ISO
Some of you will know it alredy!
I have a K-1 and maybe I will buy an APS-C Pentax too.
I also have a Sony A7 (with no IBIS). It is not heavy like K-1 but sometimes IBIS is valuable. From Imaging Resource I compared some alternatives at ISO 12800 RAW files. Pentax K1, Pentax K70 and Sony A7 (A7 and A7 II are very close).
In total K1 is best but show some WB issue, number 2 is K70 and last is Sony A7 (much chroma noise) So K70 kan beat an FF camera.....and it is low budget!