Advantages over the Chow test:
The dummy variable technique requires running only a single equation while for the chow test one has to run a number of regressions, one each for each of the periods concerned.
The chow test does not tell us whether the intercept or the slope coefficient or both are different in the two periods. In fact we cannot tell by the chow test which of the four possibilities represented by exists. In this respect the use of dummy variables approach has a definite advantage as it not only tells whether the two regressions are different but also pinpoints the source of their difference, whether it is because of the intercept or slope coefficient or both.
The use of single regression model in case of dummy variable approach would mean higher degrees of freedom vis-a-vis more than one regression models (in case of chow test) thereby improving the relative precision of the estimated parameters (but it should be borne in mind that every additional dummy variable used will also consume one extra degree of freedom).