I puchase all current carrying components through reputable supply chains. They have to much at stake to be caught up in a problem like this.
Well, there have been instances here in NZ and in Australia of reliable supply houses being supplied with dodgy "name-brand" MCB's and other important bits and pieces.
Not only does the equipment look perfectly legit, but the box they come in are EXACTLY the same (same product codes, etc) as the real McCoy.
Only way it was found out, was because a 10kA MCB was found to in fact have a breaking capacity as low as 2000A, blowing it to bits on fault.
I note that Hager (commonly copied by companies in Asia) now uses holographic labels with a watermark in them, on their devices.
But, someone is going to get seriously hurt one of these days installing this budget rubbish, more than likely without their knowledge.
I mean, would you knowingly buy and install a cheap, poorly made GFCI?, I'm pretty sure I wouldn't!