Relays and contactors using mechanical contacts/coils can be noisy, I've had several like that, and it's the nature of the beast. With cheap components comes the risk of ones that are bad. Quality control is not priority #1 when you're dealing with cheap components. That said, Auber is one of the better vendors out there for replacement and service. I've had no troubles with warranty with them, and I buy TONS of PID's off them.
I've also gotten cases of small relays off ebay where 3 out of 10 were bad, and other times not a single problem. When you're considering how cheap it is to buy one or two items off Ebay, it's not worth it to chase down warranty or try to ship stuff back cause it's bad, the shipping is often more than the item. It's a calculated risk.
When you buy domestically, it's the same issue, but at least there is local support for the product. This comes at a price though, and if you're willing to pay 3-6x more per item, go for it. The parts all come from the same factories in china though....
Or, you could do what I've done sometimes, if you need 2, buy 3 or 4. If your lucky, you got a bunch of cheap backups, if not, you're still further ahead costwise compared to overpriced, middleman marked up, same as you bought stuff, that you bought locally.