[ApK]

I have a K3 (KK) and a PW2. I keep the K3 in the Amazon lighted leather case.
I am still a lover of the page turn buttons on the K3, and honestly do not like the ergonomics of using a touch screen to turn pages.
Also, full disclosure, I don't use either of them much at all. I've been listening to audiobooks (and working through a couple paper hardbacks).

I am not totally in love with the front-lit screen on the PW2. It seems a bit soft to me, and the color cast is not ideal. If all else were equal, I think I prefer the K3 in bright room light, to the PW2.

The PW2 is smaller and lighter, especially considering the K3's cover, so that's a plus.
The touch screen, as much as I don't like it for page turns, is wonderful for navigation, dictionary lookup and other system operations.

I would not give up my K3, because of the buttons, and because the screen is very clear in good light, but if it died, and I had to buy a new eink reader, I would not go find another K3. I'd probably try a Voyage. Or, if they cut the price a lot, the Oasis.

(The PW2 is more or less designated as my daughter's at this point. )