Plus
+ Very good sharpness already at full aperture
+ Low Distortion
+ Relatively quiet, fast and accurate AF
+ Control for focusing mitigation
+ 4 x AF-ON button on the lens
Programmable focusing distance AF (Preset mode)
+ Comparatively short focusing distance and good magnification of 450mm (APS-C)
+ Clear approved bokeh
+ Relatively good lens properties
+ Feels very sturdy
+ Weather Sealed
+ Steady and balanced tripod mount included
+ Lens Hood Included
+ Cover the lens hood to access the polarizing filters

Less
- Chromatic aberration occurs
- Relatively high price
- The weight of 2.3 kg
- No aperture ring

Conclusion
Congratulations to all Pentax photographers, now there is a sharp and good super telephoto zoom for you too! The only fly in the ointment is perhaps that it costs more than the Sigma and Tamron 150-600 variants (which unfortunately do not exist with the Pentax-mount and really quite useless to be compared), but Pentax 150-450 are also generally better at the time, and higher quality will as usual be prepared to pay extra for. Too bad that Pentax is not released its promised full-frame camera yet, it would have been extremely interesting to see how it performs on a camera with a larger sensor. Anyway, we got to borrow a completely newly published Pentax K-3 II to test this loophole with, and the camera is not of the picks either.