I train with 8 reps and use a weight where i can complete 3 sets of the excersize and make sure form is good. Then move the weight up as the sets get easier.
Also for
mass building, Ladder Sets are great. Basically, you grab a weight of about 80% of your maximum lift for any particular excersize. Lift once, then rest for 10 seconds, after 10 seconds lift twice, after another 10 seconds lift 3, then after a final 10 seconds lift 2 again. Thats one set. Do this 3 times with about a 60 second rest in between sets and your body will feel like its going to explode!!
I'm a personal fan of the
Arnold Press Ladder Set *rubs hands*.