New or used cartridge

@terry9 
Consider having your Koetsu rebuilt through a Japanese or Asian deputy service. E.g. EIFL (Japan) advertises this for low-2000s on stone platinum model. Otherwise, the USA distributor & dealer will each take a hefty cut, and do nothing to expedite the process. Also, the rebuild cost does not rise for the premium stones, so the long-term cost on say a Coralstone can start to look pretty reasonable. 

I've also heard that Koetsu will not touch a cartridge that's been worked on by any 3rd party. Not sure if that still holds, but it certainly keeps me away from any 3rd part work. Over the years I've seen an awful lot of Koetsu with SoundSmith ruby cantilevers "less than 10 hours", etc, for sale.

@terry9 
They're just a deputy service that facilitates the transfer of Japanese goods. They would route your cartridge directly to Koetsu Japan (which is the only place to receive a genuine rebuild) on your behalf, just as if you were a Koetsu owner living in Japan. I haven't yet used EIFL myself, but it looks like a viable option, and I've used deputy services from Japan in the past for purchasing other goods (often of quite significant value).

@handymann
Yeah, trade-in won’t get you much unless you can use it as a bargaining chip for a dealer that’s willing to cut into his margin. Probably better off selling the Urushi yourself.

The stone Koetsus are all wonderful, though unfortunately I haven’t heard an Urushi. The differences between Onyx, Jade, and Coralstone are all relatively subtle. They each have better (more powerful and clean) bass response than the RSP. The Onyx is a pretty excellent all-rounder. The Coralstone is a slight bit more warm, organic, and fleshy sounding. It is probably the best sounding, overall, by a small amount. But they’re all great and give the full dose of Koetsu magic. Don’t stress too much over the stone differences. I highly recommend any of them!

Do give consideration to the amplification needs of a 0.3mV output platinum. The Bob's Devices Sky SUT's make for an extremely synergistic pairing with any stone Koetsus, for a very reasonable price.

Yes, Lundahls though K&K are a great deal (plus very small fee an assembled box); in my system I prefer the Sky to the copper LL1931, but I would absolutely love to hear the silver-wired LL1931Ag or LL1933Ag (or their higher gain versions) sometime. The LL1931 is certainly a great value for the money. Very transparent, airy, and detailed; a refined and grainless sound with an awesomely huge soundstage. The Skys give up a little on those things, but in return supply more body, warmth, and bass impact. I wonder how much of that sonic difference is attributed to the amorphous core (i.e. would the laminated metal core LL1933 sound closer to the Sky?). In my opinion the Sky makes the Koetsu sound even more "Koetsu", but it’s valid that some would like to take it in the other direction. The Skys are also slightly smoother and more refined than the older 1131 CineMag.

I agree that acquiring a great SUT is a good investment that will never wear out.

@handymann 
Sorry to veer off topic at various points. I can also report that I started out in Koetsu by buying used. I've gambled twice here on Audiogon with the purchase of used stone Plantinums (Onyx and Jade), both advertised in the ubiquitous "300ish hours" range, and was very satisfied with both results. Both sellers seemed to be enthusiasts, not dealers or high-volume cartridge flippers. That was several years ago, and I still have them now; I had the Onyx rebuilt last year.

Some people are adamant against used cartridge purposes, but it worked for me. Especially when you can get a full Koetsu rebuild for a reasonable cost. But I'd steer clear of the Soundsmith'd ones. 

@terry9
Dang man, unfortunately I’m on the opposite end here in Atlanta, and travel doesn’t agree with me. I’ve already come VERY close to blind ordering some of these silver-wired Lundhals before, and may end up doing so in the not-too-distant future. I guess if I were going to pick a horse right now, it would be the LL1943Ag, for the higher gain and traditional laminated core.

I already run & love pure silver for all my system cabling, and I’ve read that silver wiring in transformers makes an even bigger difference than it does for other wiring applications. Hence my strong interest in these LL's

You can reset the hour counter with a rebuild or retip, but sellers should of course state the approximate date of last rebuild/retip too (and who performed it).