It doesn't really matter if you're impressed or not but to shoot at a really dim lighting at acceptable shutter speed and giving you that kind of image for me is "more than good enugh".
Using my Softboxes and umbrellas in controlled lighting situation does not require much of the K-5 coz my earlier model like K20 and K-7 are more than enough for most of my clients requirements.
About the Impression... the OM-2, FE2,FM2, MZ7,MZ10,MZ50...etc... also gives me an awesome pictures that had matched with usually primes in a portrait mode(portrait distance). But i have to develop and print those and it takes a lot of developing solution and printing paper(money==$$$) and finally this days, just imagine i don't need to do all those and even bump the ISO at that extreme where most of film can just gives you may be a shadow but K-5 image at 51,200 as what i have in this link is just, ..just awesome.
In controlled lighting everbody is a winner (provided that you know what you're doing) b'c0z it's you who dictate how much exposure U really need.
Displaying that image is just for those who haven't tried what a pentax K-5 can do in a handheld/no-flash /really dim-lighting situation..
that's all... and thanks for the comment(even if you didn't like it) lol