Tubular control arms are lighter and stronger than stock control arms. In some instances they will help lower the front of a car while retaining a reasonable amount of suspension travel. If the tubular control arms are equipped with urethane bushings, they will reduce or eliminate alignment changes in cornering, on rough roads, etc. which usually produces strange or weird handling. If you have an open fendered type car, they can also improve the appearance of the suspension 1,000%.