Emm from CheesyCam just released a warning about the Mitakon Lens Turbo for Micro Four Thirds (MFT or M4/3). The message is clear: this adapter/focal reducer will not work on the Blackmagic Design Pocket Cinema Camera (BMPCC). Above is a video from Emm clarifying this.
[UPDATE April 2014 - Mixed reports are still coming in, buy at your own risk. It fits for some, it doesn't for others.]
He mentions that it will work fine on (for example) the Panasonic GH-series, and it is said it'll also work with the Blackmagic Cinema Camera (2.5K) - but the latter hasn't been confirmed via field-testing as far as I know.
Emm also goes into lenght about what this focal reducer might do for you and what its advantages and disadvantages are.
If you will be shooting on a BMPCC however, and you want to use a focal reducer to get rid of (at least some) of the crop factor - then the only choices you have are the ones from Metabones right now: the Speed Booster BMCC and Speed Booster BMPCC.