I own a Moritaka Supreme Santoku... iron-clad AS. Very stiff little knife, takes a sick sick edge, great profile for home, LOVE the old rosewood handle. This is particularly a knife I can't get too acute on sharpening angle with or else I really have to be careful due to fragility. No different than any other knife really, but I've heard the edge make a creaking sound before just from poly contact. It was at 10 degrees a side & silly sharp. Keep it 12-14 a side & you will be really pleased.
The Aoniko is the same knife just more durable steel as the lesser Hrc allows more abuse.
I haven't used the Takeda Funa, but I have used Takeda. VERY light knives. There is something magical about them in hand, but the one I tested for a few days had a very hollow feel to it. It left me extremely underwhelmed. Like I said - magical in hand, but just left me disappointed after cutting with it. Sort of like the hottie that sucks in bed...
Admittedly, I have only used one... Takeda.
You say, "There are probably others I've missed..."
Yes, there are scores of Santokus in the 7" range on the menu. None that you chose are stainless although all three are AS. Not to mention you say you are interested in a Gyuto, yet all three of your choices are not.
The Kohetsu 180 Santoku <--link
is a must have on my list. I have a Kohetsu Gyuto right next to me, and the Kohetsu series overall is really a game changer. It is truly a laser thin & light knife so you have to be into that style. If you are, you can't deny this knife. The Kohetsu Santoku profile though is the closest thing you are going to get to a Gyuto. The profile is utterly perfect on a 180... for me. I almost want to sell my Damascus Tsuchime Ryusen 180 Gyuto <--link
to buy it as the Kohetsu is so far superior
The Masamoto VG <--link
is a workhorse Yo-handle; I like its profile though not like the Kohetsu. It is a much heavier knife; not as if that's a bad thing - just mentioning.
A fully stainless Santoku option is the Kanehiro G3 <--link
. It's a typical Santoku profile. I have not used their Santoku, but I have their 150mm petty in this Ginsanko steel & its does all I can ever ask of it & more. Edge potential & retention truly amaze me on this product. Furthermore, their AS forge is second to none. I have two of their AS gyutos. I have used & sharpened them for years, and they are the most impressive AS steel I have ever dealt with.
Another fully stainless Santoku option in a 7.25" inch blade is the nickel-damascus clad Kikuichi <--link
in the beloved AEB-L. This is another Santoku I have not used though I have used the 240 gyuto that's sitting right next to me - quite a bit. The Gyuto is superbly thin while still inspiring strength, integrity & rigidity. I reckon due to the atypically broad neck & 60Hrc, but that's my speculation. It's a real sweetheart of a heat treat, and @Hrc60... it's really versatile! Dimensionally, the Santoku follows in the Gyuto's footsteps, and this is one of those hidden gems on the menu. I've been really impressed with the Gyuto because it performs everything w/o a comment. KISS always rings through my mind when I think about this knife. It's totally my style, in that, it just gets the job done. It is a bit too pretty for my taste, but it is also sort of awkward looking, as well; so it sort of nullifies the former con for me. Biased grain rosewood d-handles are totally my style though... I LOVE D's! This one is a bit thin in diameter for my taste, in relation to the knife, but it is not incredibly bothersome ergonomically speaking.
Also, if you're bent on spending four bills,
there are the Powder Metallurgical steels to consider. The Richmond ZDP
, the Tanaka R2, and the Saji SG-2.
MORITAKA SUPREME 170 SANTOKU STATISTICS:
171mm on the edge... (6.75")
46mm height - heel to spine...
3.2mm thick 1.5" above the ferrule tapering distally to 1.8mm thick 1.5" below the tip...