K-r：http://product.pchome.net/digital_dc_pentax_kr/sample_291912.html
645D: http://product.pchome.net/digital_dc_pentax_645_digital/sample_145846.html
via http://blog.pchome.net/article/315371.html
(in Simplified Chinese, English Translation via Google Here)
To download full samples, click on the sample gallery, select the picture and then click "查看原图", which means "view original picture". The original picture will then be downloaded in a new browser tab/window.
Although the author does make the disclaimer that those sample pics are not from production units, I have just checked that all his units are already programmed with the latest production firmware. As such, I don't think those samples would be far from what other Pentax users could get with their street units, so they are still of good reference value after all.
Furthermore, as a famous Chinese blogger on photo gear (and also an editor of the Chinese PC Home), I think the author should at least know very well how to properly use his gear (and get the best results from them)..