tomshardware[.]com/pc-components/power-supplies/redditor-finds-heavy-block-of-iron-shavings-inside-cheap-psu-also-appears-to-lack-safety-protections
Because everyone *knows* heavier means better, this article showcases a power supply [PSU] with a block of iron filings inside. That's a 1st for me, as I've only been aware of them using chunks of concrete or rocks. The more sophisticated scammers sometimes use empty shells of components, sometimes glued over existing, inferior parts.
I've long warned about cheap PSUs, as worst case they can damage the PC's electronic components &/or catch fire [yeah, sometimes both]. Very many are not UL listed, or the EU equivalent, and if they do show they passed safety testing, it's not uncommon to submit a circuit board for certification, then once certified, use a version of that board with different and/or missing components.
In a nutshell, the PSU marketplace is a paradise for scammers -- you're really not safe unless you can find a trusted review where someone has both bench tested and torn down a PSU model you're considering, *regardless the price* [it's not just the cheapies you have to watch out for]. The presence and number of safety features varies, while very many do not meet the specs printed on the box -- further, they may or may not have the advertised design features.
There are some PSU brands you can generally trust more than others, but that varies from model year to model year, and even between models. Brands that are generally more trusted for other PC components usually contract out their PSU manufacturing, and they can skimp on specs and/or be cheated by those contractors. What about the PSUs in pre-built brand name PCs? You're generally safe with brands like Dell, HP, & Lenovo, as in the PSU is Very unlikely to catch fire. But they'll use the cheapest PSU possible to save costs, meaning minimal features and lower quality components compared to what you can buy aftermarket. IOW you should be fine for up to maybe 4-5 years unless you want to upgrade something like the graphics card.