I had mixed experiences with both. On one hand, Amazon replaced my 3DS no questions asked when a shoulder button failed (Nintendo pretended the serial didn’t exist…), on the other hand my preorder of the Bayonetta Amiibo (Amazon for the EU) well… they cancelled it like six months after it got released and the support person had no idea what was going on. On AliExpress I ordered a drone that got delivered “to the wrong address” and the seller very clearly tried to scam me with helpful instructions on how to mark it as received to progress with the refund. But then I also got the logic board for my 3d printer from the manufacturer, and a reasonably priced remote controller for my drone.