Hey Spearmaster!
We are in the process of putting together a campaign with Gnuf on Casino City. They are a bunch of great people with an exciting brand! They only launched last month (around CAP Euro). We did an interview with Gustav (Affiliate Manager) around the launch and he went into some detail about the program.
Interview: http://www.gpwa.net/forum/showthread.php?t=169149&highlight=gustav
Gnuf.Biz does not go into much detail about payment percentages, but we did create a details page for them that reviews their payment methods, software, and earnings options. After this month I may be able to give you more detailed feedback.