I decided to do a test of Maxwell Render casutics after reading some time ago an article of Bertrand Benoit about it. I will not explain the differences between Maxwell Render and Vray because Bertrand has explained it very well. only one thing, Maxwell Render is an unbiased render engine, therefore the caustics are done automatically.
For the test i used three glasses with a glass material with dispersion. If you want to download the glasses, click link below, the file is an obj format.