Played a "panda" unit at a shop briefly, found the following:-
1. The unit is not as large and as heavy as originally expected when it is put in hands! It is surely not particularly small, but with a DAL 18-55 attached, it does not feel really very large neither.
2. Holding the camera is in general comfortable. However, there is a rather strange feel of holding a brick in hands as this camera is really just too flat and straight for all its surfaces, especially when every time I looked at the camera! :-o
3. The unit is solid and well built including its the built-in flash. The flash's moving mechanism and construction is nice, popping up is smooth and the flash is overall sturdy. In fact, I regard that its build is far better than that of the Sony NEX-7, which is made to be rather flimsy and has much play when closed!
4. The material of the body does not like plastic, but it doesn't feel like metal neither as it cannot be felt to be cold and hard - another "extra-ordinary" and unique "feature" again! ;-)
5. The mode dial above the chimney is magical! It is more easy to access and turn and indeed the new position is better! What a design! Now, I know that it is not only about aesthetics, but Pentax really thought about ergonomics!
6. As for the user menu, everything is almost the same. It's good as the Pentax menu system is almost the most user-friendly and easy-to-use plus fast access one on the market, which I usually like. In addition, the new Red button really comes handy for video recording, too. After all, I don't like engaging movie mode via the mode dial.
7. With the DAL 1855 lens, AF is fast and snappy in a bright room throughout the whole zoom range, which is yet another unexpected thing against what are viewed on the YouTube. I consider that the AF to be on a par with my Sony NEX. The auto-selected focus points and image positions are in general accurate (I mean at least making sense), I think.
8. The shutter lag is a bit longer which this time lag is significant and could affect actual use. There is no noticeable double shutter actuations as in other Pentax DSLRs in Live View mode, though. I guess Pentax has used a new technique to reset/discharge the sensor before exposure instead of closing the shutter mechanically. The shutter sound is clear but not really very loud. At least it is not as noisy as my NEX and yet the sound is crisp which I like.
9. The back LCD monitor is the same one used in the K-r, I believe. There is no anti-reflective coating and is not particular bright. The glare is quite obvious even at indoor which is annoying and I am almost sure that at outdoor it will be rather difficult to view.
10. The colour of the LCD monitor is in general accurate, which is one of the pros of Pentax cameras (against what Canon and Sony's cams of which the displayed images are usually rather blueish which I hate). The resolution is fine but again at outdoor it doesn't matter anyway as it cannot be viewed clearly in the end! :-x
Okay, nevertheless, I think I still will not buy the K-01, as it is meaningless to add it in my Pentax lineup, in addition to my K-5, K-r and K-x! I might buy the DA40XS lens alone shortly, though, as this lens is funny and still not too expensive. It is also film / FF compatible as well!