Well to really assess an aircraft you have to consider many things so it's really not that cut and dry. For low level strike I'd go with the B-1B, bomb load the Tu-160 takes it, electronics, probably the B-1B. Delivery systems and weapons, the B-1B. The Tu-160 is faster, the B-1B flies higher. 17 Tu-160s are in Russian service today, There's about 50 B-1s in service today. The B-1Bs are combat proven, I don't know if the Tu-160 has seen real combat