This paper deals with the simulation Benchmark multi-criteria evaluation of the performance of control strategies for biological wastewater treatment plants. In particular, the usefulness of more compact multi-criteria measures is discussed. For an illustrative selection of control strategies, an economic index weighing operating costs appears more powerful than a grey-scale presentation approach. The use of a robustness index, indicating the transferability of control strategies to situations different than the ones defined in the Benchmark protocol, is also evaluated.