I moved all my reps to 20 a few weeks ago. Big difference for me. Trying to avoid injury had lot to do with that decision too. This week I tried 15 reps on everything but settleing for no less than 12. I found that to be better for me. It let's me use a good deal more weight but still let's me concentrate on killing the muscle I'm tryin to work more so than working with an 8 rep weight.