That cow is springing, their is a slight slope from hooks to pins (look at the actual bones), she is so long hipped that I can't foresee any calving problems. A tailset like this is often the result of flushing caused by the drugs to superovulate her. I don't know whether she was flushed, but it might explain the pronounced tailset. A similar tailset can also indicate less than ideal ferility, so its something to look into before using the bull.
At the end of the day, its a matter of whether you value good doing ability in a cowherd or not, or whether you even need it in your area. I agree the tailhead is far from ideal, but I'll look into her production record first before I'll decide it bothers me enough not to consider a son of hers. If her record is sound it's no more than a fancy point and at the bottom of my selection criteria.