As a broad observation, we find that QR-BH locates the global energy minimum in either the same number or fewer steps than the pure QR search. The mean number of steps to find the global minimum (over the three QR-BH repeats) is always lower, taking, on average, 74% of the steps needed by the pure QR searches. As observed in previous work, the quasi-random search is often effective at locating the global minimum energy structure early in a search and this is borne out for these three molecules. The ease of finding the global minimum in energy is thought to be due to low energy structures having wide basins of attraction. It is for the systems where the global minimum is located later in the search that the improved efficiency of QR-BH is clearest: the global minimum in space group F 2dd is first located after hundreds of steps in the pure QR search for all three molecules, but is found much earlier -after fewer than 100 steps -for most of (7 of 9) the QR-BH searches.