I can usually hit a Silver pretty consistently, but it'll often take me a half hour per night to hit Gold on both challenges. I had a lot of problems with the extreme Dojo one last night for some reason. And Murfy's dungeon...well, I just hate the levels with Murfy in, it's just another factor in things that can go wrong.
Likewise on Diamond Ryan! I can either spend hours a night trying for a Diamond without success, or consistently hit Golds quickly for 3 months. Think I'll pick the latter