If your weigh is as you say... you're really shooting a light setup for hunting. The lighter arrows make the bow more noisy and everything. You're also working your bow at the bottom end of it's capabilities. All bows are more efficient when shot near the upper end of their range. Speed does not kill in this case. Placement, penetration and a sharp broadhead do. It'll work, but not to the optimum. I'm with whoever said you lost a lot by switching. I'd rather sneak up the poundage a tad and raise the arrow weight a little. Your old 500+ was an overkill, now you've gone to the other extreme which is REALLY hard on the equipment. It's just waiting to explode on you.