I agree w/ KBacon. Keep the bag target for field points only. Broadheads will shred the beg pretty fast.

Better off getting a cheaper foam type target for broadheads. I've been thinking about the Morrel Yellow Jacket as well.

I know your thread wasn't asking for information on this but as a side note - it sounds like you may need to some tuning to get broadheads and fieldpoints to hit together. A properly tuned bow should be able to get them pretty close to each other if not hitting the same spot.