These 6SN7 equivalents are superb when you get one that works, but the reject rate is pretty high. There is a cure, however, and that is to carefully re-flow the solder inside the pins of the noisy ones. However, they've come up very high in price nowadays, and I don't think they're much better than the JAN Sylvania VT-231s of the same era.
The product is exactly as described, sent as described, and i found it good value for money, these tubes are getting hard to find, as most retailers have become semiconductor conscious and no longer stock them.
these tubes are used in some complex electronics and to be able to find them is for me a good deal.