I would say it's better to shoot a bow you're comfortable with than the heaviest weight you can draw without hurting yourself. I can draw a 50 lb bow, but I can hold at draw comfortably with my 40 lb, and I know it's going to go where I want.
Also, in addition to using a heavy arrow with a sharp broadhead, remember that it's important to have the arrow properly tuned to your bow! I've seen guys shooting heavier bows at targets and the arrow just falls out when my arrows are buried so deep they're hard to remove. You can draw 60 lbs, but if your arrow isn't well matched, you won't get efficient energy transfer and some of that extra poundage is just wasted. Tuning is even more important with a lighter bow, where you have less energy to waste.