That sucks about your K-5. You know that I experienced the same with mine in New Zealand because I was a dumbass too and didn't ensure the battery grip port rubber cover was installed
Regarding the shadow recovery, I am similar in that I push the shadows a lot. My photography has evolved to where I underexpose EVERYTHING by -1/3 to -3 EV (in extreme cases) in order to preserve the highlights since the shadow recovery is so excellent. It also helps when I need fast shutter speeds in very low light and can push the EV by a couple stops in Lightroom. I honestly have not noticed any difference between the K-30 and the K-5, and now the K-30 and the K-5 IIs when pushing shadow recovery in post. I'm sure there is a difference (every test dictates as such), but for "real world" usage, my experience says the K-30 is more than capable at handling shadow recovery.
I used the K-30 extensively in New Zealand (because, like I said, I was a dumbass and flooded my K-5) and there were several shots that I still don't know how I managed in post because of being pushed 3-4 stops. These are two examples from the above New Zealand post:
17) Jenny and I decided to go spelunking in a large cave just outside the hut (Luxmore Cave), and I was able to get this image of the entrance from inside. I'm actually really proud of this image, as not only was it technically difficult, but I spent about an hour in Lightroom trying to get it to where it is. Friends in my office swore it looked like an ultrasound (I don't see it...). I brought my tripod into the cave (which I will review at a later time -
that tripod is amazing) and I set the camera on it and took about twenty shots at varying exposures. This I from a single exposure, and the original is completely black except for what seems to be a very overexposured entrance at the top - the K-30 absolutely blew my mind away with what I could pull out of the RAW's shadows in Lightroom.
Pentax K-30, DA* 16-50
60) And more track. Here the track descends to one of the rivers we had to cross. This is another one of my favorites from the trip. Similar to the cave entrance shot earlier, the dynamic range of the K-30 is what made it possible. This is a single exposure that was severely underexposred to allow for the beach and a small wave breaking (which are barely visible, but still), to not be blown. Then I raised the shadows within the canopy and loved how it perfectly captures the mood of the entire track we followed.
Pentax K-30, Sigma 8-16
Both were underexposed by about 3 stops.
I love my K-30, but be prepared for a MUCH louder shutter
-Heie