http://www.yaotomi.co.jp/blog/walk/2012/10/pentax-k-5iis-1st-review.html
(in Japanese)
All samples are available in full size and full EXIF is preserved even for thumbnails. ISO samples from ISO 100 to 51200 are posted, with a few other picture samples, all of which are also night scenes. Lenses used for the test are FA77/1.8, DA14/2.8 and DA*16-50/2.8.