After several messages back and forth with HMSat they assured me their SuperJack products are genuine.
I placed an order and the actuator arrived with me today, it doesn't even have a brand name, let alone SuperJack or SuperPowerJack!
I have two of those in the pictures.
The label make no difference. There are no "genuine" SuperJacks anymore. I think it's time to let go of the notion of "genuine".
SuperJack used to be marketed under the Jaeger brand, but that has been ping-ponged around for a bit, and now seems to be owned by Taiwanese company. Other companies wanting to *sell* (not manufacture), will need to call their products something else (like "SuperPowerJack").
There seems to be one or two manufacturers of satellite actuators spitting these things out in volume in the far east. So whichever the label, the jacks mostly originate in the same factory.
However, this does not means jacks are jacks.
When you buy stuff in volume, mostly made to order, you can get to decide not only what the label says ("extreme power jack"?), but also a whole range of engineering parameters that ultimately influence cost: Bearing types, metal type and thickness used, gear material, motor source (manufacturer), seal types and specs, the whole shebang.
And even after all that, my experience with far-east manufacturers is that you still may not get what you ordered - different quality components having been used, different mechanical designs etc.
So... I think that SuperJacks these days are remnants of the old days - most new jacks of roughly the same price are roughly the same performance. If you want long-life service and high-performance, you need to acquire higher quality (10x price) professional actuators like Thomson-Saginaw or some of the other American brands (eg Von Weise).
But still, the old adage holds true: You get what you pay for...