My mentality is - did we clear it? Then it was a good run. Doesn't matter if it took 10 minutes or 40 minutes. DF is a random matching system that tosses players of all skill levels together and you don't know what you're going to get. I can keep my chill there no matter what it throws at me because I don't go in with expectations. If I want to start setting requirements, then I would use PF.