[hEaT]

I don't know what the Roush rates are...but they have to be stiffer than the stock ZX3 rates at:
F: 110 lb/in
R: 117 lb/in

Because of the drop and the required marginal stiffness to be that low without hitting the bump stops during normal driving, the stock ZX3 dampers would be operating out of their effective range and with a spring that is too stiff to control well. It would be ok to start...but no telling how long they will last. It depends on your driving style, how much life is left in your dampers, etc. Hard driving with well worn dampers, 5k miles? Maybe more? It's very hard to tell, but it's not something I would run for sure.