In my opinion, thats a pretty good middle ground. My arrows weigh in around 445 grains, and I'm shooting 27", 55#. I was told I should keep it around 400 grains, but I am shooting consistent groups with very little drop over 10 yds... but I woods hunt, so pretty much all of my shots stay under 20 yards, that's whyI elected to go a little heavier for the added energy/penetration. I would say that's a pretty good weight for your combo, a good cross between weight and speed. And yes, depending on length and type of vane, most will run in the 3-5 gram range.

Darrell