Just tried the latest MLV Lite build on my 5D3 and the speed does seem comparable to the last nightly. I've long wished to be able to use the extra features of MLV, but like some others, felt the performance tradeoff was an issue.
Also, as others have reported, I too am not able to use MLraw Viewer with MLV Lite files. I just get a black screen. I realize that MLraw Viewer is no longer being updated by the original developer, but for me, it is still the fastest way to work with ML raw files. It has become quite an important piece of my workflow. While I love the idea of consolidating the .raw and .mlv formats, it would be difficult to lose the real-time previews, exposure, white balance adjustments, and lut/log output of MLraw Viewer in exchange for this. Not trying to complain, just pointing out something that may effect others who also have come to depend on MLraw Viewer as part of their workflow.
Regardless, good job to all the involved devs in refining the standard for ML raw. Your work is very much appreciated.