I have been buying HF products for 20 years and have had few if any problems, considering what they are and what I paid for them. For personal use domestic, farm, and marine they work just fine. In an industrial atmosphere surely the name brands like Craftsman or Mac or Snap-on would be required.
One tool of mine comes to mind, a 4" grinder with a 3.3a motor. Paid $20 for it. I have had it for about 15 years and it still blows and goes. I use it frequently and have gone through about 10 boxes of wheels (about 10 to a box as I recall).
I have their 6500 watt APU (generator) and like it. No problems.
When you purchase an APU you have to consider the starting current times the applied voltage for your starting loads plus any "line running amps" for units already on line. That's peak watts and the APU has to have enough capacity to supply those currents. The name in the electrical world is "locked rotor amps" for starting inrush and can be 10 x the normal line running amps.
On a 5500w unit, you wouldn't want to have a refrigerator and freezer hooked to it simultaneously. It could handle the running amps, but if both cycled on together you could overload the unit and neither compressor would start, or the more robust one only.
So don't blame the small APU if you bite off more than it can chew.