Next page: ISO Tests
As with other Pentax DSLRs, not only is image stabilisation built into the body, but so is the autofocus motor, allowing you to use any old pentax AF lens without modification.
Misread your post - didn't see the AF in "any old AF lens."
Consequently mine has.
The full-res photos don't seem all that sharp. About only high frequency components that I could find in Photoshop was noise. It reminds me of some research in the 90s on how to upsample media in ways that trick the brain into seeing a higher resolution image. I recall that high frequency noise was used to mask lost details, then your brain would then replace that noise with a very convincing assumption about what the details should be.
The high ISO photos look great. There's relatively little noise and noise suppression damage. Put a bright lens on it and take it into town at dusk.