FYI, I've worked as the analog set-up guy at audio salons, and have sent many cartridges in for rebuilding, including Koetsu.
The rebuilds from other companies, while they may work well, do not use the same items or exact methods that Koetsu does, and Koetsu will not take a cartridge in for rebuild that has been already rebuilt by somebody else. The Koetsu cartridges that are rebuilt by Koetsu are still Koetsu cartridges. Any other rebuilder yields a "hybrid" which is a Koetsu body, with the other rebuilder's "guts". They do not have the resale value of Koetsu-rebuilt cartridges, do not sound the same, and are not the same.
Anybody who does have "live experience" with this matter, already knows this.
The rebuilds from other companies, while they may work well, do not use the same items or exact methods that Koetsu does, and Koetsu will not take a cartridge in for rebuild that has been already rebuilt by somebody else. The Koetsu cartridges that are rebuilt by Koetsu are still Koetsu cartridges. Any other rebuilder yields a "hybrid" which is a Koetsu body, with the other rebuilder's "guts". They do not have the resale value of Koetsu-rebuilt cartridges, do not sound the same, and are not the same.
Anybody who does have "live experience" with this matter, already knows this.