I will make some introductory videos for the SI Maxwell plugin (and Maxwell in general), as soon as a new plugin is released for 2.7. The current one still works with 2.7, just there may be some new stuff in the new plugin
In my perhaps not so objective opinion, many render tests I've seen are done in skydome environment and 'easy' scenes, comparing with Mental Ray especially. In these cases Maxwell is fast, considering also scene setup and no problems with flickering in animations (no interpolation), it IS fast. Also there is no question of quality. The longest render time is usually in interior scenes, then again any renderer will take a long time here.
Rendering in general I think is going towards capturing the most of what you see in nature, not toon rendering or compositing 40 render passes just to get the mediocre rendering to look acceptable. Try to add accurate DOF, motion blur, GI with realistic color bleeding and feel of light, rough metals, shadow detail......then render times and quality (
and total time it took to make the final image) should be compared.