According to Chris wood, the HF and Grizzly X3's are the same thing. The specs are different people measuring the same thing in different ways. The motor is about .8HP. Grizzly rounds down to 3/4HP, probably the more honest way. HF rounds UP to 1, because 8 rounds up to 10, right?
Super X3 is the X3 except it has a nicer head IMO, only because the motor is mounted inside the head rather than hanging off to the side. It has more power in the motor, a tapping function, and a spindle tachometer. Currently there are no importers to North America (besides Syil's conversion of course). It probably makes no difference when it comes down a CNC conversion....
My conversion is going well. I just bought a laptop to run Mach3, got all my electrical stuff working. I've not felt like milling the last actuator mount for my Z axis. I've been using a bridgeport for 5 hours a day making precision shims for 2 days, when I get home I avoid the basement
. I also need to turn down the end of my X axis ballscrew, and install my ballnut. Besides that, its just installation and I am good to go.