It's in the nightlies now, and its great. 372 MB buffer for MLV, no need to use the sJpeg setting anymore (keep it on raw through the Canon menu), indicate SRM Memory under the MLV menu, and you're in business. 13 full seconds of 23.976 fps 2496x1044 (2.39:1), which may not seem like much for a full-scale production, but would be awesome for compilation videos like car shows or promotional videos. Write speed seems to be more consistent now as well, mostly averaging 79-81 MB/s on my Lexar 1000x except when pushing it to max resolution.
Seems like buffer: 4, sound off, GD off and extra hacks: On equals out to the fastest write speed and performance, although having sound on hardly effects performance. Raw_rec gives more stable write speeds but of course doesn't have the amenities that MLV does.
Still gotta put it through the paces in normal production use but this little upgrade looks very promising.