Here's the .pdf of the install for the hyfire 6ez system.
It's a relatively new product.
I personally think it's kinda hinkee since it also incorporates the oem coil and wiring along with the supplied coil. I would not want to deal with the trickledown of that kinda integration in the long term! And a rev limiter is useless for one of these IH motors. I fail to see any advantage in this system.
The "regular" mallory 6 series box May be used with any distributor known, including hall effect trigger or optical trigger. The wiring is very mainstream and these have been in use for many years. They will also trigger a variety of coils available from many sources for potential performance increase as far as kv output, but May also me used with the oem coil based upon your budget.
The msd 6 version is identical electrically and performance-speaking. Wiring is identical also.
The mallory circuit board slides into the extruded heat sink and is not sealed as such, the board itself is sealed however.
The msd has the board inserted into a cast aluminum housing/heat sink, then it's potted from the rear.
As far as "which" of those two units to use...it's a total toss-up...functionally they are identical and interchange. The only reason I'm running the mallory as opposed to the msd...it was free and a gift!
This is my opinion!