All the info you need is already in this thread....
The Shock/energy is now going to be transferred to the Weak part where the subframe meets the Body and since this area is not reinforced enough, its going to crack this part of the body... these cracks appear on stock on cars after some time and hard driving, you can be assured with the Poly Bushes, its going to negatively impact this area of the body if its not already been reinforced/strengthened .
Take the Poly bushes out and fit the Rubber Bushes.