Warning signs you have a worn out cartridge

Send it to a retipper for inspection.

You'll hear noticeable distortion on your go-to pressings. 

I have a Kiseki Blue boxed up waiting for a re-tip. 

Here's an article I wrote on the topic:

 

https://www.thebrokenrecord.net/the-fascinating-lifecycle-of-our-stereo-cartridge/

@tablejockey very good suggestion.  VAS is probably the one to recommend as SoundSmith seems quite backed up lately perhaps due to their recent relocation.  @thebrokenrecord that is a nice article you wrote.  Thanks for sharing it.  OP, If you can find a way to inspect your stylus, I recommend a twice yearly inspection under a microscope.  Insert the stylus under the lens facing up so you are looking down at the tip.  A worn stylus will show two shiny facets, one on each side of the tip.  If the stylus is wearing unevenly these two facets will not be the same size.  Depending on the quality of the microscope the depth of field may require you to move from the tip down the sides of the stylus to get a complete picture.  Digital microscopes can be purchased for not a lot of money.  Of course wear of the stylus is only the main issue so listen for sound degradation.  Some will tell you that as the stylus wears it can damage the vinyl, that may be so for a conical stylus, which starts life with smooth walls, but as it wears it will develop sharp edges.  For Shibata and fine line, however, they wear smooth so are much less likely to damage your records before sound deterioration for other reasons such as cantilever sag occur.  Again, your ears are your best early warning device.

I'm a big fan of Steve and Ray Leung of VAS, every cartridge they have solved for me or my friends has sounded excellent.

where do you live Rusty? I wanna hear that cartridge! I'm in Plainfield, NJ, 07062

is yours the modern N.S. version, or a prior version?

These specs popped up, they are for the NS version 

Kiseki Blue N.S. Moving Coil Phono Cartridge

The Kiseki Blue N.S. is the first “new style” Kiseki cartridge ever. The typical, but shorter, Kiseki body is machined out of solid aluminium, the motor is built from the best available parts today. Two years of experimenting, testing all possible choices of materials and techniques to result in a better new Kiseki Blue. A Kiseki Blue which surpasses the results of the original Kiseki Blue from the 80’s ánd of the more recent Kiseki Blue N.O.S. Only then we felt we had a reason to produce this Kiseki Blue N.S.

Specs:

Body: Aluminum Alloy 25 mm Long

Cantilever: Solid Boron Rod 0.28 mm Diameter

Stylus: 0,12 x 0,12 Nude Line-Contact Diamond Mirror Polished

Stylus Tip Radius: 5 x 120 µm

Vertical Tracking Angle (VTA): 20 Degrees

Coil: Pure Iron Coil Body

Weight: 8.15 Grams

Output Voltage: 0.44 mV at 5 cm/s

Internal Impedance: 40 Ohms

Frequency Response: 20 – 25,000 Hz ± 1 dB

Channel Balance: ​0.4 dB

Channel Separation: 35 dB at 1 kHz

Tracking Ability 315 Hz 2.6g Tracking Force: 80 µm

Dynamic Compliance: 16 µm/mN

Recommended Loading: 400 Ohms

Recommend Tracking Force: 1.8 – 2.6 Grams

Optimum Tracking Force: 2.4 Grams

That’s nice to hear, Elliot, but has anyone ever posted on this forum that any rebuild of any cartridge turned out badly?  Meaning the cartridge sounded bad or worse than beforehand? (Of course we have seen complaints about long delays or exorbitant costs, but I cannot recall anyone saying the work done by any of the many good retippers often mentioned in this space was subpar. This is actually a good thing, but what does set one guy apart from the other guys who are also doing good work?  We’re all going by our very fallible ears and brains.