Gulfstream - sim work is typically done around max landing weight so it's not like you're at the runway limited weight.
Results? No big deal if you delay rotation until V2 to V2+15 and climb out at approx half your typical pitch attitude. If you try a normal rotation and climb out of ground effective you could be in a world of hurt.
"Speed is life". Fighter pilot saying. Especially true if you forgot your leading edge devices. Flaps aren't as big a deal. Slats alone are 50-70% of the total stall reduction from clean to full landing flaps.