I always suggest 2 seperate targets for field points and broadheads.......blades are just too destructive to a target to expect any real life with a lot of shooting.
I'd suggest a Morrell "Bionic Buck" or a good bag target for the bulk of your shooting and practice with field points......then pick up a cheaper expendable target (Or a replacement midsection for your 3D taget) for making sure your broadheads are flying true.