Schorly,you "schorly" must have a good bit more knowledge of things analog than you let on,in this thread.As you do have fabulous stuff,and SHOULD have a good dealer,for support,and a more accessible answer to your question should come from him/her.
All cartridges mentioned are WONDERFUL,as you know.You will most likely get a wide variety of "buy this one" responses(all most likely accurate),yet try to best mate the specific choice to your arm's "best requirements".This parameter is important,and is best discussed with the person you ultimately buy from.This will make a fairly large impact in overall performance,and you will be somewhat protected in case of a mismatch.Trust me,mismatches happen,and can ruin a good rig.
Since you DID ask,there are other fabulous choices to consider.Lyra's "TITAN i" is a wonderful performer.I've heard it lots.The Transfiguration Temper's are fabulous,too.As is the Dynavector XV-1s.As are all designs mentioned,already.Actually in lieu of the great performance from so many current designs,it's not such a stretch to simply go for the cartridge with the best pricing,assuming it is one of the "Recommended" designs,and works well with the arm(an arm I LOVE,btw).
As a point of consideration,I recently got an E-mail from a dealer(I forgot who,but he supposedly had tons of great online feedback),who offered the following prices on new cartridges,which really caught my interest.
Transfiguration Temper $2050.
Koetsu Onyx and Koetsu Jade Platinum $4000.
Koetsu CORAL (list $20,000)for $9995
The Shelter's were well priced as well!
The Koetsus you mention,were also at about half U.S. pricing.Actually I have a copy of the site in my car(just remembered,REALLY)and am going out,in freezing N.J. 55 degree weather,to retrieve it,so hold on.............OK--I'm back.The site is-- Hope this helps.
Looking at this list,now additional prices--My Sonic lab cartridge(supposedly #1 in Japan $2750
Koetsu Urushi Tsugaru $$2400
Koetsu Blue Lace $9995
Koetsu Tiger Eye Platinum Diamond(for the big spenders)$6500
Urushi Vermilion(red)$2500/alnico magnet
Shelter 90x$1950
Clearaudio Goldfinger $7200
Clearaudio Stradivarius $2750
this guy also is asking really good prices on a variety of ultra pricey cables,as well as stuff like Avalon/CAT/and Jadis.
BTW--I only kept this list to show my friends,who live in Brooklyn.I am NOT endorsing ANYTHING here,but thought some of "YOU GUYS",like ME,would get a "KICK" out of it.
I have NO association here,but just wanted to mention that a large discount can be had,as cartridges are usually marked up quite a bit,with some careful looking around.Surely "Schorly",you must have some good audio pals who can be of additional help.
Best of luck,and you will have a great analog ride!!