which to get next?

on a budget, would like to upgrade in near future from the K30 DSLR I have.

with the K3 coming soon, this will of course influence prices. in an ideal world I would also like to have two bodies.

at airshows I get tired with lens swapping. one idea is to get another DSLR body to have my 18-55 on while my main body mounts the 50-500 body for the main shooting.

another idea is to have a pentax Q on hand for closer stuff when I need to and only have one DSLR.

I was always under the impression that the K30 sensor was the same as the K5 so it was essentially K5 lite.

would getting a K5 get me an improvement on the K30 in any way, or do I really need to upgrade to a K5IIs or down the road a K3 for an improvement?

I'm a K30 owner too. In your position I'd get another K30, just to maintain the same button layout etc. Heresy I know, but I prefer the K30 handling to the old K7/K5. And yes I did used to own one (K7).

having another k30 makes sense, but that are a number of cheap k5's starting to appear on ebay and elsewhere so maybe a K5 makes a good buy as the K30 commands good second hand prices still.

I just seem to remember that the K5 has more features than the K30 although they run the same sensor, so I would benefit slightly but still be confident of good shots like I have now.

K5II better sensor and faster AF?
K5IIs no idea

one thing I do miss from the Kx I used to have was pressing the green button and having it take a shot and showing me a histogram without actually saving a shot. took a lot of good shots that way by getting to meter before taking a shot.

have identical bodies. I tried using 2 different on a shoot and it don't work. You forget which body you're using and fumble

K30: 12 bit, Safox IXi+ (video sensor, from Nex series)
K5: 14 bit, Safox IX+
On balance for a two body set up, like you want, another K30.
One body, very likely a K3...

K5II Series seem more accurate again but no faster, at least not to me but maybe a bit surer? (All my lenses are SDM, So I doubt it would drive them any quicker anyway!)

Agree with Smeggy, you want two as similar as you can...

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So true.

:::

How do you mean the sensor is from the NEX series? I was under the impression it was essentially the same sensor as the K5ii. In fact I thought all these 16MP sensors from Sony were pretty much the same, the main difference being the imaging engine they are hooked up to in the camera.

Yep!
The whole shebang comes pretty much as a unit out of the Nex 5n, obviously there is some Pentax snake oil involved too but they got the Sensor and the twelve bit milbeaut image engine in a oner...
Designed from the up for video, live view, peaking etc.
There is at least four versions of this sensor/image pipeline, two 14Bit and two 12Bit and two different 16Mp sensors...

I'd guess that the same electronics aren't always available for more than a year (Everyone updates!), and some of the changes may be forced by what's now available on the market.

Many cameras use the same basic sensor units. Some use the same basic lens units.

And the same batteries, chargers etc....