Amazon does much better then Wal-Mart, but in either case I’ve found the best experience is to only buy products being sold by Amazon or Wal-Mart directly. I love the idea of facilitating small businesses selling through Amazon and Wal-mart, but in practice the feature is just abused by fraudsters, scammers, and disaster profiteers. The few legit sellers on either platform often don’t deal well with customer inquiries or returns. This is why we can’t have nice things.
I’ve had mostly good experiences with Aliexpress though you have to read the fine print on everything very carefully - I think most people would have a lot of problems with that. There have been a few times I ordered electronic components and received ladies handbags or, hilariously, a toddler size leather miniskirt. I did get a refund in all those cases but it was a multi week process.
I did think it was pretty funny that the same tweezers CVS sells for $7 a piece in midtown Manhattan costs 5/$1 on Aliexpress. Only difference is the CVS tweezers are available immediately whereas I had to wait 20 days to receive the ones from Aliexpress - though I more or less have a lifetime supply now. :)