My 580 alto is a very playable instrument. It's just beginning to show signs of minor spotting under the lacquer after 5ish years, but still looks good. Having all the stack adjusting screws, it's very easy to live with. It has an acceptable if somewhat bright tone and I would expect the same from the tenor.
If you go for the matching tenor it should feel the same in your hands and have a similar soundscape.
Chinese horns don't have much of a resale value, probably around half what you pay for it, but they do make a great back up.
Bear in mind how old the YTS23 is. It could be getting on for half a century. A new horn is, well, new.
Having said that, I went for a lightly used YTS25. It was the price that swayed me. I'm very happy with it.