Raul, I do not think that a newcomer to the hobby should have to worry about whether or not the cartridge he received is ’as advertised’. The OP is obviously not short of a few dollars, and he can afford to let others worry about that. It’s a cost-convenience tradeoff, with knowledge tipping the scale towards one side or the other. Personally, I would only go with a trusted source - but to date I have only bought new.
As for US cleaning, I clearly stated that I US all records, new, NOS, or used, because of contaminants which can be observed on some of them, even new in plastic. Further, after playing a record for a few years, I clean it again. Don’t get enough grunge off to detect it, but I don’t want to risk my stylus.
Obviously, you disagree. Fine. Enjoy.