Originally posted by stillshunter
I know some would say that it seems a step backwards...and I'd be glad to hear from people that think so. I'm seriously contemplating the move from my K20D to the K-r.
It depends on your priorities. I have the K20D and K-x. From tests seen so far, K-x and K-r have identical IQ. I prefer the look of K20D images at anything below ISO 1600. The K-x blows out the reds and yellows easily, especially at default Bright image tone and Landscape, which I use a lot. The K20D colours are more deeply saturated at any given setting and the warm colours do not tend to blow. That's probably why the K-x WB is set so cool. Blues are pushed, so that Daylight WB often looks very blue. Here's a low ISO comparison I posted. I used Portrait mode, my default, because it's a nice balance between dull looking Natural image tone and overstated Bright tone:
Picasa Web Albums - Dan Bonhomme - K-x K20D
Matrix metering is useless on the K-x, it routinely blows highlights. I only use CW. Spot metering is buried in a menu, so I only use it when I have to. So are AF-C/AF-S. My favourite K20D modes, User and TAv are unavailable.
I sometimes prefer the K-x for its small size, but the downside is it's unbalanced with a large or heavy lens, and no grip available. Balance is even worse with a flash mounted. Pentax said there will be no grip for the K-r either.
High ISO performance is often overstated. I make it 2/3 stop in favour of the K-x, and from DXO testing, K-r is the same. Of course that difference can be critical. The K20D has a problem focussing in low light without AF assist. I prefer flash for low light when I can manage it, but it's not always possible.
I almost never shoot in high speed burst mode, but it's important to some people. I leave my cameras set for low speed burst. My normal shutter action takes one photo and I raise my finger before the second shot. If I see something I like, I keep my trigger finger depressed and shoot a low speed burst.
As far as build quality, there's little to debate. I don't have a WR lens now, but that will change soon.
To summarize, I much prefer my K20D. When I buy my next camera, the K-x will go, the K20D will stay. The K-x is a tool for me, I've never fallen in love with it. I carry it when size is important, and for low ambient light shooting. Since my K20D will be replaced by another top level Pentax (K-5 or better), the K20D will likely only see studio and flash work. I'm skeptical that even the new cameras will beat it at low ISO for skin tone and saturated colours. Already there are signs that the K-5 blows reds at default Bright settings.
If size and high ISO performance is your main reason for considering the K-r, it may be worthwhile to wait a few months. There are strong rumours that there will be a Pentax mirrorless announcement in the spring.