haha, my helmet has been in three wrecks now and i still wear it. I think i will see how many it takes. NOT. Naw, i just ordered a new one about 3 days ago. 2 of the wrecks weren't me but the first one was. damn that hurt.
i dont think the foam really loses its ability to take a hit, its just the padding around your face and head start to wear out, making the helmet not fit correctly. but i think as long as it fits correctly and has no structural dmagae it should be fine