2. their new version produces substantially different images compared to the old
clearly we have a contradiction, which necessarily implies that they are cutting corners or have bugs in their engine. at any rate, there is consistent error in the image not due to noise (i.e. converging to different results), and as long as this is so their claim to fame of being unbiased is false advertising.
I'm not a maxwell defender but this is absolutely wrong. That only means they have better integrators and weighting scheme than before (and than indigo) - (which is far from trivial you bet otherwise every unbiased renderer would be the same). If the results are different and one has more components, then the previous one was missing something and was bugged.
