There could be camera shake and some focus issues with the K20D when I did this little comparison. Both shots where taken on a tripod and I could of used MLU to decrease any mirror slap issues. I wasn't trying to do it like a lab experiment
This was just as a quick test to see the capacity of the Q with a high quality lens like the DA300.
I let the K20D use spot focus. So it could of picked a slightly different area than I did using the manual focusing on the Q. Sharpening on the K20D is at +2. The images where not PP'd in any way. The enlarged K20D image was increased by approximately 350% in photoshop (no wonder it doesn't look good). Files where saved as max quality Jpegs.
I think the K20D image at 1:1 looks pretty darn good (open the attachment) and if you enlarge any image by 3.5X it is going to fall apart. I'm a graphic designer and I work with digital images every day. We never increase image sizes if we can help it and if we have to we'll keep any increase in image size to under 150%.
I'm no measure-bater but I think the Q with the DA300 produces a nice sharp image. The K20D makes nice sharp 1:1 images, but if you want the subject the same size as what the Q produces, it can't keep up. The thing is the Q has limitations since the focusing is so cumbersome. So anything moving faster than a snail is not going to be captured very easily with a Q.
I guess I wanted to address the sensor issue that a lot of people rag on. Even without comparing the K20D images, the Q w/DA300 is capable of producing very acceptable IQ.
I'll do some tests with my Da50-150 next when I get a chance. Initial shoots look good so far.