first of all, their not right, they are weak. I have damaged them doing circuit repairs that would be fine with normal resistors, particularly bending them out of the way. Package engineering is HUGE and its dictated by COST. They made it cheaper not better, you can make garbage run for a while. And again, it does not work on breadboards well, its not good for hobbyists. It's not fine for manufacturing either, because then you should specify a real 1/6 watt resistor if you need less power lol
how to avoid scams? Look up 'resistor manufacturers' on google. They will give you a datasheet
btw amazon is not a great company and not a great employer.. not sure you should associate with them on stuff that is a known problem.
I should do a side by side over load test to see how they burn up compared to each other to see if the core is the same. Connect both and ramp up the wattage to see which one goes first, and how it goes, then do a pulse over load test to see the failure mode there (explosion characteristics, to see how much it will damage the circuit its in)
I also have a hunch the leads are not electronics grade oxygen free pure copper, more like recycled pipe fittings. Another test you can do is get a real 1/6 or 1/8 watt part that has the same diameter lead, and then do a back and forth bend test to see which lead breaks faster. This also messes with the temperature coefficient of the device I think, so if you do the whole precise matching thing, you might be frustrated with drifty results if you think you can get a precision circuit on the cheap. Also the plating might be low quality, so it could make solder joints brittle.
I also noticed the epoxy coating or whatever is more fragile on the cheap ones, they tend to fracture the ends when you bend them, this is a recipe for low moisture immunity and stuff if it compromises the package during part fitting prior to soldering.
Then you might also want to test the paint, see how the marking paint holds up to elevated circuit temperatures, to see how repairable the part will be if it runs hot, fades the paint, then burn out, so you are left with a unlabeled dud in the circuit. Good resistors often burn out but still have legible markings.
and when I measured them, their TCR is all over the place as compared to factory made resistors, which do much better then the datasheet usually, when comparing metal film to metal film. Batches do not line up, meaning unstable deposition I think, possibly also meaning poor film adhesion and low reliability.