NOTE!
I trided to order some TLE2072 from China once.
They were all fakes and did not even come close to the specs for TL072.
I can attest to this, especially when ordering electronic components from
aliexpress. They have independent sellers there and a lot of fakes. Be especially wary if a deal seems to good to be true. It
usually is.
That being said, there are legit bargains that
can be had there as well (aliexpress). NOTE: some sellers sell used parts but do not say they have been desoldered. So, from my experience aliexpress is a mixed bag. Buyer beware... unsure of other Chinese vendors myself. Pretty sure ordering from amazon will yield similar results as with aliexpress as far as quality or lack thereof.
BTW don't buy resistors there at aliexpress. Cheaply made and very thin leads. Tolerances are ok, but .... cannot be used in solderless beadboards for prototyping. Leads are just too thin.