Only reasons to do so would be if:
1- You're FOC is too high and you are not getting acceptable flight.
2- A particular head you are wanting to use is only offered in 100 grains and using it will not adversly affect arrow flight via FOC issues.
3- You want to pick up 3-6 more FPS (depending on the bow and how it's set up).
Sounds like you're good to go...
