Both? That could be a team slot wasted. It is much safer to go with one, as you will be able to use more Pokemon varieties. I suggest some Pokemon like these would be good on a Sandstorm team - Reuniclus, Metagross, Nidoking, Donphan, Skarmory, Jirachi, Scizor, Heatran, Mamoswine, Landorus and Magnezone