Can anyone suggest the most efficient way for dealing with Overlapping Sets questions on the GMAT?

The

Manhattan GMAT suggests using a double-set matrix for two sets and a Venn Diagram for three sets. However, I have found that the double-set matrix, although very accurate, is extremely time-consuming to construct, while using Venn Diagrams for simple two-set problems is much faster. I have also found that the Venn Diagram for three-set problems is very accurate, but also time consuming. Is there another way?