The Carl Zeiss Jena zebras are classy and great lenses (I'm biased, I admit), but once you go zebra, in no time, you'll find yourself wandering the streets, muttering words like "Flektogon" and "Biometar", looking for change to feed your Lens Buying Addiction.
I'm not familiar with that particular Sigma, but since it's a PK-A type, it should work fine with the K-01. Just leave the aperture ring in the 'A' position, and all of the camera modes will work. If it weren't an A, then you'd be limited to manual mode. Because of the crop factor, the lens will effectively be a 24mm, and while there will be
some fisheye distortion, it won't be very 'fishy'.