Nothing you have compared compares to the wiim amp. An amplifier module and a power amplifier.Not really. They are amplifiers and should do that properly within their respective design envelope. It is easily possible for very cheap chip amps to perform nicely with proper design. I earlier linked to an amp costing about a third of the Wiim amp that doesn't have load variance.
Wiim has a suite of impressive features all within the cost, in no way can they compare.
You can get a hypex module for more money but then you will need a streamer, a preamp, a dac (with hdmi arc) a parametric equalizer, a bluetooth receiver....
No comparison based only on frequency response makes sense, because this is not a power amplifier nor a simple integrated amplifier.
If you want to make a comparison tell me how much the equivalent would cost in terms of functions but with a final amplifier without load dependency. So it would be comparing apples to apples