Pentax K-3: likes and dislikes??

As others have mentioned, it is an overall awesome tool. All things being equal, I think the 24 mp sensor is slightly superior to the earlier generation 16 mp sensor because the added detail yielded gives you more resolution even after added, careful noise reduction. Getting the best out of the sensor is trickier, and takes some practice with a quality RAW converter.

Things you don't often hear that make the K-3 especially good:

1) The built-in flash gives you a lot flexibility to do fill, avoid pTTL if desired, and pair as a controller.

2) The screw drive is faster and heavier duty than earlier designs, and the resulting AF tracking with a good telephoto lens or zoom is better than generally believed - if you set up the AF tracking and focus array properly for the specific purpose (not as easy as you might think, unfortunately).

3) The video is better than earlier Pentax cameras - by a good margin. Not pro, but certainly good enough for typical needs short of full broadcast quality. Audio using mic and phone jacks is quite good.

One downside not often mentioned:

The camera does at times suffer from very minor mirror slap or shutter vibration seen (at pixel level) on occasion from about 1/50th to 1/125th. Seems to show most at 1/80th. Not severe, but real. I tend to use my K-01 more in low light situations where I expect to be using those shutter speeds a lot. Obviously, never a mirror slap issue with that mirrorless body.