Is there anything that makes it worse than AliExpress, eBay or Amazon?

They are very much (ab-)using the old get-you-hooked-by-loosing-money-then-slowly-crank-up-the-prices-til-it-hurts-when-you-have-a-monopoly trick?

The others were never as aggressive in their quest for monopolies and made it on some other merit. Not to say the others are much better, but Temu will have to make that money back somehow, eventually.

Basically price-dumping to destroy the competition and gain market share.

I somehow doubt they're going to destroy Amazon anytime soon. The market they're in reminds me more of Blue Apron/Hellofresh than Uber/Lyft. May as well take advantage their funders' bad bet before the river.

Don't need to "destroy" Amazon to be successful. Just need a few percent of sales.

What I've noticed from Aliexpress reviews is that a lot of reviews are from places that don't have much of an Amazon footprint (e.g. Russia, E. Europe, Mid east).

The other thing is that ship-from-China circumvents a lot of duties that can be hefty on some goods. And sometimes sales taxes (not in USA anymore, but still true elsewhere).

Will it make Amazon nervous? Then I kind of like it...

Also, is wish.com the same thing as temu, or basically the same thing? I mean, there's some tungsten ring for 50 cents on it that like another poster I might buy that and 20$ of other things just to see what actually arrives.

Tungsten rings are a bad idea if your ring needs to be cut off. If you ever injure your hand/fingers wearing one, remove all rings immediately, but especially a tungsten or other hard metal ring.

FYI a tungsten carbide ring, although it cannot realistically be cut off your finger, is brittle, and can easily and safely be snapped with a pair of locking pliers (locking to avoid clamping down on your finger). You may be thinking of titanium rings which are not removable in this fashion and thus are less safe.

ah, good to know. That method and another (not as great, but maybe more at hand method) here: https://www.youtube.com/watch?v=eKxUYvKR-jw

and a more proper (and $$$) method: https://www.youtube.com/watch?v=MqupCjkNqUk