Actually its 3 stops plus and 3 stops minus. In addition, if you want to have the 6 stop range at the bottom end rather than the top end, that can be set in the ControlTL utility.
Because the Einstein is controlled using IGBT technology, Hyper Sync is only useful at full power. Below full power there are both front and rear curtain shadows.
One minor benefit, the MC2 does appear to permit sync at 1/250 on a Canon 5DII.
Bottom line, they work.
There are some inaccuracies on the Pocket Wizard site. They apparently copied and pasted material from the Elinchrom STE2 material.
Here is an image that was shot using MC2 on an Einstein, CSRB+ with AC9 on an ABR800 and MiniTT1 with AC3 on a 5DII.
The Einstein had a 36" deep octa knockoff and the ABr800 had is diffusor without outer reflector.
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