I know the K9 and K18 and the later produced Adikt.
I was always under the impression the K9 and K18 are produced by Audio Technica.
Many years past I was familiar with the K9 and K18 in use.
The K18 is an attractive MM, It is using OCC Coil Wire and Lead Out Pins, it has a Ogura Styli and as model is sharing some of the Traits of the AT MLX150.
The Adikt is different, it has a more Substantial Body, a different structure and has opted for a FG Styli, I have no experience of this Cart' in use.
I have Linn MM's, AT MLX150 and a P77 Cart', along with a few other MM's, stored for when I am done with the MC side as a device to trace a modulation formed in a groove.
In recent years, using the Tonearm I have chosen to use, there is seemingly a lot on offer from the MM Cart', (yet to be ascertained) as a certain Model of MC Cart' that has been well liked, but has failed to really impress on a Variety of Tonearms, has shown when in use on the arm of choice, it is a absolute stonker, and extremely attractive, especially when it shows a real Kinship to much more expensive family members from the Brand.
I have tried to paste a recent post but failed to find it, I feel confident there is a recent post on here where a individual has had a 'rebuild service' do work on a Same Brand MM and MC and the impression the rebuilt MM has made is very satisfying to the user, it has been claimed to compare favourably to the MC of the same Brand.
A Punch above it's price Cartridge can be acquired for reasonable monies if the rebuild route is taken. Using a 1000hrs for a Cart's Life, a Cart' coming at $00.40-$00.55 per replay as a division of Cost for a Rebuild Services work, can and has been proven to function comparatively to a Cart' with a $3.00 -$5.00 cost per replay.
As the rebuilt Cart' might be an older model from a Brand as a Donor Model, it might not have the cutting edge materials or Technology on board, but as some services do refer to 'equivalent' it does suggest an alternative material 'might' be used at the time of the rebuild and who is qualified to say this is not a later generation material that is a cutting edge substance. .
I am yet to have a direct conversation or pick up on any communication where a rebuild done by a Time Served Technician with the Necessary Skills has failed to impress an individual in receipt of the work carried out.